I know that, my point is that they don't have the tools to do anything other than defederation right now.
If any users from other instances than those two act in the same way and they happen to be from other big instances, they'd have to defederate those too, because they have no other tools available.
And they knew they won't have other tools availalbe when they created their instance, so they should've created such a platform in a place where they actualy had the tools to run it like they want.

Which would've been a classical forum in my view.
Like they want to have a community where they can proactively prevent people from posting offensive things.
That would be the ideal case for a forum where you have a manual registration proccess like they have now here. Because here their registration process doesn't help when you can just comment from another instance.