I'd rather play a game with a dozen truly well-made levels built by actual designers, than a game with millions of proc gen levels that all feel like proc gen.
Well, suit yourself.
Thankfully, there are enough games for everyone.
But your weird crusade against procgen, which in truth only boils down to "I don't like it" or "this is badly done procgen" is getting really weird.
In truth, proc gen doesn't really give you more variation than hand made levels. Usually it gives you less variation, actually. If you take something like Thief or Dishonored, you have 10 to 12 hand-made levels of which each one is unique. (And in the case of Thief you have 1000+ fan-made missions, of which at least 20% or so are actually good and also have their unique style and touch.) If you look at dungeon crawlers like KotC, Grimrock, Might and Magic, etc, you have meticulously hand-crafted levels and encounters, and each encounter is designed to be a decent challenge at the level you are expected to meet it at, and there are puzzles to solve in the dungeons.
Puzzles suck in RPGs. Actually, puzzles are probably what I'd put as my worst RPG travesties.
If I want to do crosswords, find patterns or solve lever puzzles, I can buy a puzzle book for children. Or play hidden object games. Which I actually do, when I'm sick and my brain is high on meds
Memorable encounters can be had in procedurally generated games as well, I don't think I need to point you to specific threads/videos/stories/etc. about memorable things that happened RimWorld, Dwarf Fortress, Kenshi (not procgen levels, but other kind of procedural content), or any other (good!) game with procedural content generation. And those come in great variety and did not require meticulous hand-crafting for each and every one of them.
Morrowind's hand-placed loot and BG2's hand-crafted unique items are often cited as some of the best itemization in RPGs ever. Meanwhile, people can't stop complaining about how lame and boring the randomly generated loot in Divinity: Original Sin is. Getting a "unique" item (which isn't truly unique because some of its stats are randomized) feels less impactful than in BG2 or Morrowind because it could drop when you kill a boss... or it could not.
That's all true, but also all down to the fact that, as you wrote, you connect unique items in BG2 with the struggle to get to them (and partly their really unique power).
D:OS itemization is shit not because it is procedural, it would be equally shit if it were the same every single time. Even uniques suck in D:OS2 because they become too weak to use after you level up once.
None of which is even related to procedural generation.
As if it was impossible to put unique items (truly unique items, that were designed by hand with a backstory, etc.) behind a specific challenge in procedural generation. It sure isn't - though, it isn't usually done. But then that is just bad design, not anything that would lie in the nature of procedural generation.
If you want to say that bad design often goes hand in hand with procedural generation, then I'd even agree. But that just means that there are a lot of shitty designers who are too lazy to design good levels so they use procgen as a "quick" bandaid. It does not mean that procgen itself sucks as a tool.
As for your claim of levels having more variation, that is only partially true. In a game with hand-crafted level design, where you have 5 level designers each contributing 3 levels, you'd end up with 15 distinct levels, each with its own personality and style. And these levels can be vastly different, both in content and in quality, which leads to such discussions as "which Thief level is your favorite?". In a proc gen game there are no favorite levels because nobody is ever going to see the same level as any other player (unless you can specify the random seed manually, but it's still not the same). In proc gen games, you usually get 3 to 6 different layouts or styles of level. Say, you get the "dryad forest", the "undead crypt", the "demon underworld", the "warlock tower". These are the four types of dungeons you will encounter in the game. Almost all roguelikes do this. Even Dwarf Fortress does this. And while the actual layout of these places will vary, the overall style will stay the same. Dwarf Fortress has these pyramids, which will always have a similar (but not same) layout. Villages in DF also have similar layouts every time. Etc.
This one I agree with. Well, except that even if you have 5 designers x 3 levels, you won't necessarily end up with truly unique things, only in the best case scenario. We've all seen hand-made levels so bad that I'd take even mediocre procgen over them.
The time a level designer invests into a big level, a programmer invests into a "kind of level" - which then has more variations, but similar styles. That games with procgen typically feature only a handful of styles instead of dozens is something that I hope will be rectified at some point (*cough* *cough* ask me again in two years *cough*).
There is a lot more variety in hand-designed levels than there is in proc gen.
There is (typically) more variety within a single hand-designed level than within a single procedurally generated one. Yes. And by extension, typically the same is true for a single playthrough.
But after you have seen that single level's variety, that's it - it will hold no more surprises for you. Takes a lot more to see all the patterns and variations in different instances of a procedurally generated level.
Obviously, that requires a game that you'll want to play through multiple times, or that requires many restarts, etc.