This is a reading comprehension issue. Look at what I said more carefully, I am implicitly supporting the idea you are trying to help your kid and telling you to argue from a standpoint of human benefit rather than sovereignty. With the rise of Christian nationalism, we’re only going to see an uptick in “children are the property of the parent” style reasoning, and we should all be fighting it.
The marketplace of ideas tends to be a much weaker force than “what are my friends playing?” I’m all for treating kids as people, but that also means understanding that people mostly choose what lets them get on with their peers the most easily.
Minecraft seems like the obvious choice for kids who liked Roblox. Terraria is another. If they can only play on a server that one of them hosts, then no need to worry about outside users.
Good on you and the other parents for getting that shit out of there, kids don’t need addiction machines trying to pressure them into spending money.