You could argue that I suppose, but then who is doing the subsidising? For a real town square it's still the townspeople paying, it's still their tax contributions. For nostr the current user base is not covering any significant part of the costs of providing what it is consuming, in any way, roundabout or direct. The whole thing is run on a Deus ex machina plot device.
If you're not paying for your use then you are the product, always and forever. At the moment most people on nostr are not paying for their use and therefore ARE the product. The only question is to whom are they selling themselves.
The answer is they are selling themselves to a relatively small group of people looking to make a certain mark on the world, to leave a certain legacy. If enough in this small group give up this quest (this can be a mercurial sphere) then they will be left with nobody to sell themselves to.