From the bits and pieces I've been told about it's a lot of managers picking favourites, and being super restrictive for some livers while letting the other livers have less restrictions. Niji routinely bars and punishes streamers for mixing their past life, and current life too much. For example keeping connections, mods, or even commissioning people from your PL. If management things you are going too far they will restrict and punish you if you continue to far with your PL.
However this isn't the same for some of the other livers who can post freely on their PL, have previous mods from their PL modding their stream, and commissioning people their PL used. This sort of behaviour has created cliques and groups in Nijisanji that routinely kick rocks down at the other livers. Management is slow, and doesn't prioritize the livers they don't favorite.