Oh boy! Megaquote time...
The key problem: "skill point" systems don't actually end up doing that. As 3e demonstrated pretty handily, it becomes "you must be at least this tall to ride," and it HARSHLY punished anyone who fell behind. Skill points were way more of a "treadmill" than 4e was, they just made it LOOK like it was a viable choice to fall off.
Because it shows general learning. You may not be a professional cook, for example, but in general even without actively pursuing better cooking skills, you pick up knowledge over time. Fantastical PCs should be that much better. Sure, your "clanker" Paladin (as a friend of mine calls them) won't be able to sneak past people like your Rogue colleague can. It's not your wheelhouse. But if you need to sneak past some relatively mundane folks, well, now you get a chance to show that yes, you are in fact better than you were before.
That general, passive learning is a great tool in the toolbox. It gives insight and context for their growth, for their journey as characters.
4e does all of that, except that it allows for small, minor growth outside your core--passive learning. So you can see that you've grown from your adventures, and not just in your ideal preplanned ways.
Eh. 4e did a pretty good job of avoiding this (despite claims to the contrary, mostly by folks who had no idea what they were talking about.)
Because power creep. Dunno if you've ever seen or played a high-level PF1e party, for example, but good Lord almighty it's a nightmare. I've had two DMs burn out trying very enthusiastically to run high-level PF1e. People often talk about high levels not being supported; part of the reason they weren't supported in the past is that, in 3e and PF, those levels are just too damn janky to support. You started seeing that trend even before 3e. I'd even argue that, before 4e, the last time D&D really properly supported high-level play was friggin' BECMI.
Because the increased challenges are different challenges other than the ones you faced before?
Like...how is this difficult? Threats you used to deal with still exist. They're just generally below your notice now, because you have bigger fish to fry. The people who make FFXIV actually did some really cool work with this concept, since narratively it applies just as much to D&D-inspired video games (including MMOs) as it does to tabletop gaming. Specifically, in the previous expansion (Shadowbringers), the relatively one-off "capstone" quests for each class (formally, for each job, as that's the Final Fantasy term) gave insight into events that were going on while you were separated from the world and doing separate but vital stuff. One of the things revealed in some of those quests is that some of your allies, who have the same "can't be mind controlled by big nasty summons" protection you have, have been leading the charge to deal with the aforementioned "big nasty summons" while you're preoccupied. They explicitly refer to it as "putting out the small fires" so you can stay focused on the larger picture, because you've graduated beyond dealing with these threats.
Having such moments, where you can look back and realize how far you've come, is an extremely useful tool. And not just in fiction. I've worked with several students as a tutor in mathematics, some of them over the course of multiple years. I distinctly remember one young woman who was working on a calculus question of some kind, and it was clear from her face and gestures that she was getting frustrated and angry at herself for not being able to do it super quick. So I asked her, in a very rapid-fire kind of way, "What's the sine of pi/3 radians?" She said, without missing a beat but a little confused as to why I was asking: "...Square root of 3 divided by 2?" And I told her, "A year ago, that question was hard. Now you can do it in a flash. That's how far you've come." The look of shock and relief on her face was delightful.
It's genuinely a shame that, in the quest to quash even the tiniest, vaguest hint of "treadmill," we have thrown out such a valuable tool.
Correct. The problem is, what about when you're inventing new things, because you're writing a brand-new adventure for level 15 characters? 4e had a clear answer: there is a set of tables which tell you what ranges values should fall in if you already know that this adventure is written to be an interesting challenge for level 15 characters. But a lot of games that strive for "static DC" design try to have their cake and eat it too, and it results in an arms race between power creep and scope creep.
Yep. Again, despite the claims of "treadmill," 4e actually had an internal concept of a character's arc. It's why, if I ever make a 4e "heartbreaker" (more like "4e with Ezekiel's House Rule Module"), one of the key components would be merging and expanding Themes+Backgrounds into Heroic Origins, so that you'd have a full character arc: Heroic Origin says where you came from and how you got started as an adventurer; Paragon Path shows how you outgrew your humble beginnings and became a renowned exemplar; and Epic Destiny tells how your great deeds left an indelible mark on the world.
Because D&D has been extremely combat-centric for decades, perhaps forever (the old "heist" style focused on more strategic-level combat rather than tactical-level combat). It has also, historically, struggled heavily with non-combat abilities and spells, either making them so weak as to be pointless (e.g. the spell augury is often nigh-useless) or so strong as to trivialize anything you use them on (Rangers are often accused of this in 5e, for example.) There are several systems out there which both place less emphasis on combat alone, and handle non-combat stuff in a more effective and productive way. Of course, familiarity is a powerful thing in TTRPGs, so just because other things might work better does not mean they would necessarily work better for your group, at least not right away.
If we can say this of 3e, then we absolutely should say the same of 4e. 4e wasn't a treadmill, and anyone saying it was a treadmill simply misunderstood how to run it, even though the books were quite clear about these things. (E.g. explicit instructions NOT to use only encounters tailored to the party's level, but a mix of encounters across a fairly broad range of levels, e.g. anywhere between level-4 and level+4, favoring high variety.)
Because, honestly, people want the "read a novel" part to be dispersed uniformly across the text. Even if that's neither easy-to-use nor productive. Or at least that's what I've come to see from this discussion thus far. Well, that and people (even ones who stridently defend "DM empowerment" and "rulings not rules" etc.)
If this is what people have meant by "rulings not rules," they've done an absolutely terrible job of explaining it for literally a decade at this point. This doesn't, in the slightest, look like "rulings not rules" to me. It looks like treating the rules as an extant baseline, and then building new things on top of them. It's not that you're treating the rules as mere suggestions with no validity. Instead, you look to them for grounding, and build upon them with additions where you need such, only overriding or overwriting them when a serious issue comes up. That's a hell of a lot more cautious than any presentation of the "rulings not rules" concept I've been presented with.