I think we’ll still have companies limiting speech on Nostr. The key is that users have a choice about who regulates the speech they see. “no one” is a valid answer but isn’t the world most people want to live in.
Discussion
The difference is that the individual is free to choose relays. Sure, you won't see every pornographic picture on every relay, but you could always choose a relay that does transmit every pornographic picture or every note from the POTUS. If not, the sex worker or POTUS could run their own relay.