DkS 2 is great. I mean just compare to every other console game that isn't a Souls game or Bloodborne. It's a fucking odyssey of Jap ARPG punishment. "Odyssey" is probably a real consolefag-ish thing to say, like calling a game an "experience," but whatever. It's like an ambitious sequel to a classic movie, where the scope is greater but it's not quite as sharp, as some would say of T2 or Matrix Reloaded (DkS2 is actually a good follow-up though).
And that was part of the problem: they doubled down on what they thought people enjoyed about the series, like getting raped, and did it in a thoughtless manner. What was considered hard-but-fair got turned into hard-but-fuck-you, here's this room full of cock knockers and statues spitting poison, with a couple of black phantoms and an invade sprinkled on top -and they're all aggro'd, bitch. Or something like that. Inelegant design, basically.
Well, that's a bit imprecise, since the "holds-you-down-and-stuffs-something-down-your-rear-end" bits of Dark Souls 2 were by far the best parts of the game. The problem is, there wasn't much
else there - the original Dark Souls did have the harsh difficulty, but it also had way better exploration and a sense of wonder and accomplishment that came simply from discovering new places and things. One important thing was how areas had clear themes - most notably, the Catacombs and Tomb of the Giants were about Miracles, the Depths and Lost Izalith were Pyromancy, Duke's Archives was Sorcery and Oolacile was Abyss. This made the areas a whole lot more coherent and allowed for more meaningful item placement too, which again made exploration feel more relevant. Of course, the neat and fairly sophisticated inter-connectedness and soft gating of areas during the first half of Dark Souls also had a big role in this.
Dark Souls 2, on the whole, had
much less of those things, which also led to worse environmental storytelling and a worse ambience in general. The result is that the "unfair" bits in the gameplay stand out more, and it doesn't feel like the game is
rewarding you as much, because the item placement was erratic and most of the stuff wasn't too interesting anyway. So even though the game is really good, and no harder than DS1 was, really, it feels more like a masochist grind because you didn't have those euphoric moments of revelation when you climb your way out of the Depths and realise you're at New Londo Ruins.
As for Dark Souls 3? Hell yes, bring it on.