Sorry, I don’t really remember anymore… I haven’t played D1 since it came out nearly 30 years ago. I did recently try D2R for a bit before putting it down again, preferring the modern games instead.
I’m a genre fan who thoroughly enjoyed both D3 and D4 for a while, because they enabled late game build variety without as much grind as PoE. I loved the exploding chicken build in D3 and the silly one-click builds in D4. What they share is mindless fun, where once you get the build going, it’s pretty much just running across the screen at max speed and exploding everything with a single click or two. No skill of any sort needed.
It’s the opposite of a hardcore experience. I don’t play it as a skills test, more something like an idle battler, and in fact I’m the opposite kind of player to you… I don’t spend months and years getting good at these games. I learn the basics in a few hours and then jump to the endgame via cheats, bots, or real money transactions. I’m only interested in their build permutations, and in that sense both delivered enough variety for two or three months before I moved on. I think I ended up spending more time writing a web crawler to look for item trade deals than actually playing the game… because that’s what I needed in order to make the build I wanted. It became more of a marketplace simulator.
By contrast, PoE2 and PoE 1 in Ruthless mode are more about movement, dodging, skill combos, and generally tedious gameplay that tests how good you are at reactions and button pushing (I’m not).
PoE1 in normal mode I think is generally a game with more lasting power. It has the same build and item based fun as D3 and D4 but with far more maturity and content and depth.
Last Epoch to me is the best balanced of them and the most out of the box playable. It has great quality of life features and good crafting and moderately complex gameplay that still has sufficient end game complexity. I played that and PoE1 way more than any of the Diablos.
Grim Dawn and Titan Quest felt more like D2 to me in that they emphasize passive point allocations that slowly improve skill power, making it so that you basically have to do math to calculate the optimal distribution. I don’t really enjoy that and prefer systems where each point makes a meaningful, visceral difference — as in “this point makes explodey things, and that one adds a shield”, not “adds 0.5% to dmg”.
That sort of system is what prevented me from wanting to reinvest time in D2 after I first played through it as a child. D3 and D4 by contrast both use more modern point systems that don’t waste your time allocating trivial passives. Last Epoch isn’t as dumbed down and still has a few passives, but the max point per skill is like 3 or 4 instead of 20+. PoE1 has that crazy passive tree, but there it’s really more about the keystones (the bigger nodes with more important functions) and jewels (items that modify the passive tree) than the small passive nodes. Unfortunately the game has a shit new player experience so you really have to watch videos and read and study to understand the mechanics, but once you start to, it’s incredible. Nothing else like it on the market.
Sorry I couldn’t answer your question directly! Just providing what info I can.
If I had to choose one game for someone coming back to the genre after two decades away, for me that would be Last Epoch. D3 and D4 are great for casual players but I don’t think they can hold someone’s attention if they are used to the old school games… they’re just too easy.
But none of these are bad games. Far from it. They’re all subtly different but each was a labor of love that can deliver fun for weeks and months. Even my least favorite ones among them I still played for 20-30 hours, which is way more than most non-ARPGs I play. My favorites end up getting played for hundreds of hours over many years. They’re all good games in different ways. Maybe watch some gameplay videos and see which one appeals to you? Or try them all! They all go on sale from time to time, and PoE1 is totally free.