I disagree, why do you think Nostr fails if there are only a few apps out there?
The benefit of having a single protocol respected by all apps still trumps what we currently have with single individual silos. If you don't like Damus, you can switch to Primal and still have your account with all your history. Try doing that with Facebook and Twitter.
Sure, EU's DMA tries to fix just that, but currently only for messaging apps, not social networks. The issue with that approach is that they're still trying to connect individual silos, each with their own proprietary architecture, which hampers interfunctionality, instead of relying on a single, shared protocol like Nostr.
Realistically speaking, if Nostr truly succeedes, people won't be using 200 Nostr apps, but more like a dozen or so, as it happens in any other domain. And that's still totally ok. Because people can at any time go ahead and create a new app that will work with the rest of the Nostr protocol if the dozen or so existing apps go all nefarious at the same time.
I've said it before, I'll say it again. People need to start working on better onboarding and marketing for Nostr if you want it to really succeed, instead of bickering over useless things or fantasies like legal contract signing apps and worrying about situations that, in the grand scheme of things, won't even matter if this thing doesn't take off the ground first and actually start having users.