because if your friends start roaming around the public Matrix network and find public chatrooms full of abusive content, then they will indeed be affected. see https://matrix.org/blog/2025/02/building-a-safer-matrix/ for more.
So much so that it’s looking like maybe federation is not the best model. Your server ends up hosting any room and potentially any media that any of your users gets into. So naturally server admins must take an interest us in what their users are doing. This is in conflict with the top level goals of freedom and privacy.
Maybe the simpler client-server model of the web is better after all. Then if some user on my server is also into some super weird stuff, I don’t have to know. Because they connect to the weird server directly from their client, not through me.
1. The Matrix Foundation wants to promote communities to encourage adoption.
2. Matrix needs tools for moderating communities, even if the Matrix Foundation doesn't run communities.
So it probably does make sense for the Foundation to take this problem on, even if not directly required to making a chat protocol.