I run QOTO, an instance that strongly leans towards open federation, but locally doesnt allow free speech (our users will be banned for certain forms of speech, though we are rather forgiving in this regard).
While we do sometimes have valuable interactions from free speech instances the issue is the overwhelming majority of interaction is from them dog piling and trolling with overtly racist and aggressive attacks. It is often so bad you cant even use the service without blocking most free speech instances...
Blame who you want but even an instance like QOTO that wants to remain open is struggling to do so because it just makes the service unusable.