I agree, this also doesn’t take in to account that relay use cases can grow. If I subscribe to Medium, then I can access Medium articles. But say I were to subscribe to a premium nostr:npub1yzvxlwp7wawed5vgefwfmugvumtp8c8t0etk3g8sky4n0ndvyxesnxrf8q relay that content locks certain articles: this will also be able to accept all forms of nostr comms.

If nostr:npub12262qa4uhw7u8gdwlgmntqtv7aye8vdcmvszkqwgs0zchel6mz7s6cgrkj is correct then costs scale with user numbers, not usage or content size. Therefore paid relays can have a base case and peripheral cases that support other parts of the nostr protocol without impacting subscription profits.

At least that’s how I understand it