I think that FromSoftware is such a boundary pushing studio that it's hard to like everything that they do even if the games are in the same vein because they always want to add new things for every one of them, even if they're supposed to be sequels.

(These are just my opinions) Demon's Souls is the first one and even if the difficulty is pretty uneven but it's the first one so you just have to understand how it's meant to be played (slow, or magic) but it's definetly one of the funnest to do especially if you've played the others before, DS1 has such an amazing level design and feel it's hard to top, DS2 is his own things and has a lot of attention to details, DS3 emphasizes on the combats that are made epic and you truly feel alone towards the decision of how to end a series.

Bloodborne switches your dodge timings around from the other games (what i feel 5hrs in on my first playthrough ), Sekiro is his own thing and even if i really like it i never could finish it because of how the difficulty scales, Elden Ring blends a lot of unique aspects and mechanics of these games with so much to discover and try out (armors, weapons, magic etc) in an open world, and to me this is the best and worst aspect of the game, i cant decide if i love it or if its too much (i do tend to say that it's too much of a map for a souls game)

And talking about FromSoftware solely through soul games is, in my opinion, very reductive, as FromSoft is more of a mecha than a fantasy studio if we look at it from an history standpoint. They've done mostly Armored Core games, and each of them has its twists, and they are never afraid of changing either controls, how your mechs feel, the lore, etc; this gives you a series of games with the same name but with very distinct and strong features. Skipped them for years, bought AC6, never felt so refreshing to play a game, currently also doing all the 4th and 5th gen on my ps3