in games with lots of human or humanoid armored foes the weapon vs armor type rules are more impactful. I like systems like that, especially as they relate to making the "boring" fighter more interesting and making weapon choice about more than damage potential and the shield bonus trade off.
Comrade!

I knew I wasn't quite alone in appreciating those obscure/maligned rules.
You throw these out and your drastically reduce the capability of the fighter, because they are the ones that have weapon versatility. Instead every fighter walks around with a long sword.
To be fair, they end up running around with two-handed swords (or maybe the odd bec de corbin or Lucerne hammer), until they realize the random treasure tables are dropping lots of longswords*, then they end up walking around with those, instead. But, by then, it's tool late to change their weapon specialization (especially in 2e, when going with double-specialization in a weapon you could dual-wield in pairs was the fighter's killer** app).
This is a bit off topic, but I wonder if people coming new to D&D in this era do that as well. Is houseruling a thing in the era of streaming games and Adventurer's League?
Very much so, but /outside/ of AL. (I suspect the same was true of the RPGA when it got rolling - while 2e was very likely customized to the nth degree out in the wild, you couldn't really run organized play like that.)
That's what a lot of people assume, but it's not actually true. The "Hovering at Death's Door" rule was explicitly an optional rule presented in the DMG. The PH says the character dies at 0 hit points. Most people may have used it, but it's not in the core assumption and I find it interesting that the game stepped toward more lethal territory in 2e than 1e in this respect.
It was an option in the 1e DMG, also, so I'm not sure how it stepped towards lethality by keeping a similar rule? The 1e version was pretty brutal, too, with a mandatory week-long recovery...
… and what was the -3 threshold about, again...? … it's teasing at the edge of my memory...
5e has PCs that have more power, and start off with more power at level 1 than 2e, but for the rest? I guess that depends on what your definition of "heroic" is.
Also when it kicks in. And whether it has 'posthumous' in front of it.
IRL, "heroic" often means facing great odds or terrible challenges, and dying, with or w/o out accomplishing some/any of what you were struggling for.
In a story, "heroic" often means facing what appear to be great odds, and overcoming terrible challenges, all with the understanding that no one would be telling the story if you'd failed. If the story is fiction, and not a classic or post-modern-grimdark tragedy, the audience prettymuch knows it's going to be written so that the hero survives insane odds so he can triumph by the end. "Plot armor," it's sometimes called in fannish circles.
Since heroic /fantasy/, by definition, has no choice but to be fictional, it very often shakes out more like that last sense of "heroic." I say "very often" because there is stuff like GoT out there, when a character is set up like he's going to be the hero, then killed off.
D&D, traditionally, was not very heroic. It was a fairly cynical to comically paranoid exercise in treasure-hunting and one-up-manship. It was cooperative in the sense of rivals working together to survive, while competing to come out ahead when the treasure & XP was counted.
Not that nearly every group was like that, of course, but it's very much how the game was presented (I'd hate to try to count all the times EGG cautioned that the players would "naturally" want to do something greedy, cowardly, unethical or amoral), and what a lot of the talk in what passed for a community (as communicated in 'zines & The Dragon & such) seemed to assume.
But, D&D /did/ model plot-armor, but not for the guy designated 'Hero' at the outset - as no one really was - but as you got higher level. Hit Points and Saving Throws were the mechanics that modeled plot armor, and you got more of the former, and lower targets for the latter, as you leveled up. So D&D models the latter sort of narrative hero - eventually (really, in the 'sweet spot'). But you have to pay your dues first (in the classic game, survive 1st level, maybe finally get a name at 5th, as the old joke goes - in 5e, well, by surviving 1st and exiting Apprentice Tier and entering the eponymous 'Heroic' Tier, at - funny coincidence - 5th level).
Point being, 5e is even more faithful to the classic game than it might seem at first glance.
* "I can keep using my non-magical bec de corbin, or the +1/+2 vs giant weasels two-handed sword I finally found, or I can choose from the +3 frostbrand, the sword of sharpness, or one of the six other magical longswords we've found over the last 8 levels..."
**pun so totally intended.