That could theoretically happen, but do you have any actual examples?
The easiest example is that D&D 5E design places zero value on different methods of movement or movement speed.
The default mindset behind the design is that being able to teleport, fly, or move any number of distance every round does not in any way impact CR. While that may be a minor detail, it is a detail that is central to how encounters, adventures, and monsters are built to the game, so it echoes throughout the other mechanics of the game. One of the core "whys" of the game's design leads to creating mechanical building blocks that combine to create unintuitive design results from the mechanics.
Modern D&D also has taken a lot of steps to try to streamline things like stealth and perception. In theory, the mechanics used for 5E's skill system and codifying a character can do something are better mechanics. But the end result is a bit of a convoluted mess that often defies any common understanding of even simply being able to see something. Even with errata and updates to the 5e24 books, the end result still often doesn't make a lot of sense.
Magic and Magic Items are another example that comes to mind. While modern design has taken steps to better codify things and fit into modern ideas of game design, the end result is less fun. Certainly, maybe older systems lead to things that were imbalanced and maybe even unfair in some cases, but modern +N slots just feel kinda bland and lesser than how things were handled in older design. Fun is a subjective thing, so this is a weak example, but I play games with people and read the forums. I'm not alone in my views on this.
I think the issue is too the closest things I can think of to being examples are like reverse-examples, where either an older game did something clunky, but worked really well for vibes, or an older game did something clunky, which technically made a lot of sense for describing a situation and had good fictional outcomes from how it worked, but like, took literally dozens of times more to resolve than it should.
I agree that some older designs took more steps. Whether or not those more steps actually take more time than the current "streamlined" approaches is debatable. I play mostly D&D. Modern D&D combat is more streamlined but it takes longer to achieve less. I do occasionally play other games, but not often.
Sure, maybe we don't still have convoluted grappling rules. That is an improvement. But needing to look up one area of the rules that takes a little time is overall worth it in comparison to sessions dominated by combat that drags.
Supposedly, modern game design has learned that a game feels more fun when a player is able to hit a certain percentage of time, so hitting has been made easier to make the game (in theory) feel more fun. But then the way chosen to accommodate that is to scale monsters by giving them more HP. I'm told that all of these changes are based on modern principles to make playing the game more fun. So, if I'm not having more fun, I don't know how to explain that.
Recently, I tried Daggerheart and had a similar criticism about how damage is handled in combat. Responses to my criticism of there being extra steps involved in determining injury was other people saying that is intentional so that people can feel good about having big numbers like they have when playing D&D. That's related to the % hit comment above because (again, in theory) those choices are based upon some modern design idea of what "feels better" for modern players. Personally, I do not find that those modern sensibilities feel more fun.
I did enjoy aspects of Daggerheart. I am only bringing up that criticism here because it is related to this conversation.
So in one case it worked out okay, and in the latter, it was a disaster even though it "accomplished"* something that a modern game probably wouldn't.
I think magic and magic items would fall into that for me.
I'll give you the actual examples, because I've asked for such:
The first is Friday Night Firefight for Cyberpunk 2020. It's a slightly clunky and slow system, but for all that, it does feel like you're actually having a gunfight between futuristic people wearing various kinds of body armour and with very varied kinds of cyberware, and not so so slow and clunky as to completely take the wind out of things (unlike 2020's netrunning system, which is godawful for everyone involved including the netrunner and GM!). The results I would say are better than 2022's Cyberpunk RED somewhat bland combat, but Cyberpunk RED doesn't actually attempt to apply modern design principles and approaches sadly, it's basically just FUZION 2.0, stuck 20 years ago, just not stuck 30+ years.
The second is Millennium's End, a 1991 RPG which took a magnificently insane, self-indulgent and iconoclastic approach to gun combat by having you:
A) Look at number of drawings of people, with numbered regions, and picking which one best represented the target from the angle they were being shot at (this lead to... disputes...)
B) Get a transparent plastic overlay, and putting it over the drawing (I forget if different guns or fire modes had different overlays, but they might have).
C) Roll the dice to see where you hit, then getting into an argument about whether it was really a miss or because the hit area was blank but very near the body or because the hit area was actually a line between two body parts or the like.
D) Check if you penetrated any armour/cover (there may also have been a chance for the bullet to deflect at this point, I forget).
E) Try to work out exactly what kind of injury you did.
Was it doing something modern design wouldn't? Yeah absolutely. Was it worth doing? Absolutely not. Was the combat better than contemporary games like Cyberpunk 2020 even Twilight 2000? Not even slightly, it was if anything significantly worse and more painful.
But I await your examples.
Thanks for those examples. I am not familiar with those games, but I get the idea.
I think this is true but I think it's impossible to suggest that isn't very common in 1970s and 1980s RPGs, which were often designed with truly insane and historically completely wrong takes on how melee or bow combat worked, and often designed thoughtlessly, in ways that failed to allow for events that were downright common in the fiction or setting they were supposedly emulating (a good example being that few 1980s and even 1990s fantasy RPGs allowed you to sneak up on someone and stealthily take them out, even though it was relatively common as a trope in fantasy of that era and before - one of the fascinating modernizations of Kevin Crawford's Worlds Without Number is that it creates a sort of "OSR compatible" way to do this). One of the changes of starting point with more modern RPGs tends to be "What are the thing that happen in this genre/setting/era?" and "How do we make sure our game makes it possible for them to happen in the right way for that genre/setting/era?", where a lot of 1980s and again even some 1990s and 2000s RPGs are just "Here's a system we like, let's try and jam some stuff we think of from this genre into it, and just kind of forget about the other stuff!".
* Accomplished in this sense like you might "accomplish" going to the supermarket by phoning four friends, getting them to build a palanquin from you out of wood scraps and loose nails, and then carry you around Tesco.
I think it is good to take genre conventions into account. However, I also feel that a genre convention should be discarded if it often grossly violates what makes sense in a given situation. That's more of a personal feeling. For example, I do not like when an otherwise intelligent or proficient TV show or movie character is suddenly a moron (or incompetent at their usual niche) for a few episodes because the story needs them to be for a plot to work. I mean, yeah, sure, we all have our boneheaded moments, but not like that. It's an accepted trope in a lot of shows, but I still hate it. The Boba Fett tv show was pretty bad at this; apparently, he just forgot that he had a jetpack during the various episodes when enemies would trap him in an alleyway.
Likewise, some of the later Mandalorian episodes featured a tribe of Mandalorians who were supposedly deemed hardcore and extreme even by the standards of other Mandalorians, so you would think that they would have no problem with basic tactical tasks. Instead, they couldn't figure out that maybe they shouldn't send their kids to play in water where a giant monster was eating them.
Rather than trying to force the character to be an idiot to suit the genre and the plot, I feel that it would be better to change the plot so that it does not require violating an established part of how a character normally functions.
I know that's not game mechanics. But I think that problems that I have with that clash of expectation VS result can also be found when playing RPGs. If shiny new mechanics produce results that are at odds with what makes sense, I would rather stick with the old clunky stuff.