damage is no problem at all if you're actually able to roll and not get greedy with hits. Same thing happened to me with those guys, tried to tank hits thinking they were easy. When I came back after I died I picked em out 1 by 1 and got through them easily. If you get forgeted by enemies hidden behind walls it's your fault for rushing through. You need to have a sense of awareness, granted not as much as DS1 with Sen's fortress for example, but still. And after high wall of lothric and the puny hollows that do that you should be prepared. The enemies that do large amounts of damage are either fat and slow, and have an attack that locks them in a direction (ex: the big fat harald dudes) or the angels which are stuck in one place, with the game giving you plenty of cover to get by. I do agree camera tracking is an issue though.
enemies doing a ton of damage is the big part of dark souls that makes it hard, but that doesn't mean those women with books in the undead place being able to throw out a move that does a ton of damage and has super armor on it out of hitstun animation is fair
it doesn't take skill to kill those guys it just takes way too long because you never know when they're going to hit you with a book from hitstun
not to mention almost all mages / hunters have unlimited resources and will never run out of magic / tools / arrows / bullets to use against you, have way too much health & damage that wouldn't be able to be achieved through regular builds, etc
also regardless of whether enemies behind walls are a problem to me or not, brume tower is the perfect example of hidden enemies and artificial difficulty in dark souls
the big ash fields? the second you step onto them you're being shot by magic while 2 - 3 knight guys pop out of the ash
iron pass? get through three something rooms with 4 - 5 knight guys, mages that use unavoidable magic that weighs you down, and mages that shoot lightning and magic at you (mages that you can't kill unless you also use magic / ranged weapons)
that room with the big fire shoulder mallet guy, archers and knight guys you can see from those balconies with cages on them? either abuse i-frames by opening the door or die
that entire dlc is just bologna and i still haven't beaten it because i refuse to trudge through the iron pass fifty times to be rewarded with one of the most boring bosses in that game
it's not like dark souls is completely bologna difficulty but from software definitely makes games that have a lot of
completely unfair stages that just take figuring out the cheapest trick you can do to beat the stage rather than playing the game better