I'm guessing the misconception is that all those creators would run public free open-to-all relays and face huge scaling/moderation/legal costs. That's obviously a bad idea and won't happen. 

But does an average wordpress site have "comments"? Yes. Does author have to moderate those comments? Yes. All blogs are already tiny "relays" that have some costs that creators pay for. Again, nothing new.

If nostr is adopted, creators will have relays to host their own content, and to host legit reactions to that content - other events just won't be accepted. It will require some moderation and some costs, but that's a completely different thing vs managing a big public relay.

And outbox model will deliver you the twitter-like experience even though the content is scattered across a hundred relays hosted by creators you're interacting with.

Will there be big relays? Yes, twitter will run one, meta another. Will creators rely on them? No, not exclusively. Creators will run their own, that's the whole point. 

And if DNS/hosting provider kills their relay, they'll just rebroadcast their stuff _everywhere_, until they set up a new relay in a different place. 

Thanks for coming to my TED talk, as they say.