if cover announce Hololive Alternative as gacha you have your answers why they get rid of Coco.

It did not simply pass the china censorship.

china is always one of the top country spending money in gachas and cover is just a corpo. Account balance is the only thing that matters, nothing else. Well it's not secret knowledge or so, but some people still belive corpos "care" about their talents or anything else than money.

They will get rid of any girls in Hololive to keep chinese money.