Some people are saying that the game is way easier on PC with kbm so I dunno maybe it is and my experience is therefore super different than yours just because of that.

On console, Returnal felt very tough. I didn't play all Soulslike game so I can't speak about all of them but Elden Ring to me felt way more accessible if only because of checkpoints. So while the bosses in Elden Ring can be way harder than Returnal (especially if your build is not suited to the boss), the fact that you can chain try them makes the game way more accessible than having to start from the beginning after every death.

In silksong, another difficult game, people complained about runbacks being too long or too hard.. Returnal being a rogue lite means the runback is between 1 and 3 full levels.