What about the Brave browser[1], which works at the application level? Or Blokada[2], which works at the OS level? Or Pi-Hole[3], which works at the network level?
I haven't seen even if they specified whether it must be the account user or not. E.g. your network host or isp can do it.
So that seems interesting, unless they can do it on a whim anyways and dont have to prove anything. Though they could just say, "no free service if we cant serve ads".
They can block service for whatever reason they want.