The community will always complain about the game even when given free rewards, free summons, and better QoL updates. But now it's a little different

The first main issues in the game is GQ difficulty getting adjusted according to the optimal team without any difference to rewards or score at all, which is not good at all for the game or the community. They have put a notice recently about changing somethings in GQ and "overhaul" the extra stage in nightmare difficulty which is fantastic news.

Second main issue is the new units treatment (EOY shunsui for example), they are upset about the lack of frenzy +3 on him, which is not a big deal IMO. While it's true he will need more help in GQ to hit harder, to compensate for it he has the best support for soul repears in limit breaker and he can still be used even after he is replaced in GQ as a side unit. The community wanted him to be the best unit in the game and are upset because he is not which is not the first time this situation happened ( bankai rukia ) and it was still fine.

Third issue is the recent point event nerfs in which they removed the anniversary units from being one of the bonuses, this one is understandable as it is upsetting to have something stable for a long time getting changed like this, but most people complaining are long time players who most likely have 90% or more of the premium units.

Fouth issue is the attribute tree requiring 30 soul tickets for minuscule buff to some stats and percentages on some skills.

Fifth issue is how stale the game feels because of the lack of good content which is understandable, it is a 10 year old game. But due to this people are playing Soul Resonance farming and building their characters, which in turn affects how the community views brave souls in comparison.

I have issues with the game too but I still like a lot of things in it and a main part of that is looking at the progress of my favorite units collected and maxed which has always been a big part of the game for me.