IMO, relays should be note-agnostic. Anything that interferes with that is going to curtail the free transmission of notes, whatever the kind. Setting aside the very obvious flaws in the following analogy, relays should just be the connected backbone to allow you to make phone calls. They shouldn't stop you from talking about "illegal" things. It should be up the the client to decide what to reject "listening" to.

These are all things that need to be hashed out before building an extensive mesh network as an alternative to the internet.

Obviously there are considerations for t relay operators, but I would suggest that if someone isn't able to make a principled stand and risk jail time or execution for freedom, then, well, they shouldn't be offering a service that has that potential.

Limiting liberty should only be done at the individual level. Offering a service to others is no longer an individual enterprise and should, IMO, be done as freely as possible.

I'm still noodling this over as I'm sure it's not as sound an argument as it should be.