The overarching change is that fewer and fewer things have negative effects other than just causing hit point damage. 3e had quite a bit of save-or-die in both items and spells, but not as many things that had other nasty effects e.g. limb loss. 4e lost a lot of the save-or-die but still had spells and items that could cause damage to stats. Curses are almost a thing of the past now; the game allows the players-as-characters to be far more trusting.
The other thing that plays against funky effects at the design level is the strange desire in all the WotC editions to codify everything under pre-set "condition" keywords e.g. prone, stunned, grappled, etc. I don't think they have a keyword for "down a limb".
Yeah, a lot of costs/risks have been removed from spells - e.g. lots of spells (haste, wish, restoration, gate, etc.) age the caster in 1e, I suppose also implying a system shock check. Raise Dead lowers Constitution etc. It is always nice when you see a 5e spell that still has a hint of risk/surprising consequence: Teleport can have mishaps, getting hit by Prismatic spray can send you to a random plane, Reincarnate can bring you back as a random race... nice to see little idiosyncracies nodding to Vancianism still lingering when many spells have had the rough edges and quirks sanded off.
The need to codify everything in a preset condition I think is a lot of my issue with 5e magic. Preset Conditions are great as an efficient, memorable way to package effects - used well, they can actually reduce the mental burden of abstractions and keep the focus in the game world. But I think they can degrade things when designers assume just about everything has to fit into one of the preset conditions, or (even worse), think of the condition first, and ignore whats going in world, or assume textual flavor has no bearing on the effect beyond the condition.
That's why I house ruled that HP IS actual "meat points", and tracking it is for "active" use only. Your characters are in a fight that they're aware of (even if surprised). But out of combat "scenes', HP doesn't matter. That antagonist pointing a crossbow at your face in the tavern? You actually have to worry about that, narratively. Even if you have 100HP.
Yeah, stuff like a crossbow in your face is tough to abstract with the 5e hp system as written. I usually assume hp are a mix of luck, fatigue, and superficial wounds - reading old records of premodern battles, you do hear of armored soldiers get hit with multiple arrows, be fatigued and lightly wounded, and be able to carry on fighting, but still need healing after battle. That's the sort of image I have in my head.
I think the crossbow situation and a lot of other pathologies of the hp abstraction are helped by alternate routes to death beyond the hp to zero -> death saves. 5e has Max hp reduction, disintegration, and ability score damage with the score going to zero instantly killing you, but these are relatively rare, and the first two still need to eat through hp. It's why the Strength drain of e.g. Shadows is so refreshing as a monster ability. I think the earlier edition Save or Die (from e.g. poison) effects represented this sort of routing around hp - even if you are beefy, the right poison doesn't care about your ability to not get hit. 3e (I believe) actually had a possibly 5e compatible way of implementing the crossbow to the face with the Coup de Grace, with some nice preconditions/risks:
I'd prefer to have something like this than contrive something like a super high damage crossbow bolt just for the occasion - as an abstraction that keeps hp in its proper place, this sort of thing would sit better with me.
While limb loss is certainly a downer, I would certainly like to see D&D embrace an optional system that accounts for the chance of such grievous wounds - opening up a host of options for mundane items, spells, magic items and more.
The 5e 2014 DMG at least (maybe 2024 too?) does have a nice optional lingering injuries table (with limb loss, eye loss, festering wounds, etc.), and they are pretty good as far as these things go - give some nice justification to the Restoration spell! But yeah, because it is optional, it becomes mainly a DM fiat sort of thing, the effects are almost never worked into spells/items/monsters.
I'm not actually a DM that is extremely into ultra punishing lingering effects all the time, but I do like that it broadens the scope of possible effects, and marries numerical changes to concrete effects. I think the ideal is having a good spread of durations across different effects - some lasting a round, some an encounter, some a 10 minute dungeon turn, some a day, some days, some weeks, etc to give different sorts of weight to consequences. But this really goes from hassle to making the campaign feel more alive when time (at multiple scales) matters, semi-regular downtime is expected, and there is an expectation that players have a stable of characters they can draw from when their character is out of commission for a few weeks - aspects of the game that have either less rule support or less of a play culture supporting them in the current edition.