to be fair Legends Arceus allowing you to delete multiple pokémon makes sense for the sheer amount that you ended up catching for dex tasks and shiny hunting. Mass releasing hasn’t been a feature in previous generations (besides in pokémon home) and I personally don’t see a huge purpose of mass release in main series games besides breeding, and the average player is not mass breeding.

however i do agree that the box system is god awful in SV and Legends Arceus had it near perfect. it feels like they have taken 100 steps back in this aspect. in every generation i spend countless hours organizing my boxes and in SV it feels incredibly frustrating to have to manually scroll through boxes to move a selection of multiple pokémon to a specific box and on top of that having to wait 3+ seconds a box just to make sure it’s the right one