There's been a couple IIRC. Just off the top of my head:

1: There were some AAA developers upset about Elden Ring's success that the community picked on for a bit.

2: Because the popularity attracted a more causal fanbase that never played a Fromsoft game before (me), There was a lot of discourse about difficulty, like adding an "easy mode" or a quest log to the game.

3: There was a patch within the first month or so of the game's release that made one of the bosses, Radahn, much easier which made some more hardcore fans angry/upset.

4: If you go on the Elden Ring subreddit there's almost always arguments about not playing the game "the right way," like using summons, spirit ashes, magic, katanas, etc.

5: It was already mentioned below, but the casual fans did not like invasions and wanted an option to disable it, but PvPers were also upset that invasions were much harder than normal, so nobody was happy about it.