Perfect example. You do realise that nobody will use Nostr for legal contracts (as if in its current form, a Nostr note can be recognised by a government entity as being legal, which is absurd) if Nostr fails as a social network first, right? This is what I’m talking about… Focusing on extravagant ideas that might never materialise.
Discussion
So, your point is that a court accepting Nostr as a legally enforceable contract is dependent on the success of a Twitter app using Nostr. Now that's absurd.
The basic elements required for the agreement to be a legally enforceable contract are mutual assent, expressed by a valid offer and acceptance; adequate consideration; capacity; and legality. If those elements are in place, you can write things in a napkin, without even signatures, that will be enforceable. Nostr conversations by themselves can become enforceable contracts. It doesn't matter if the twitter app succeeds or not.
A contract requires a valid signature in order to be legal. That signature can either be hand written or electronic (using software specifically recognised and vetted as a trust service provider by the government), depending on the government rules. In some countries, a notary is also required, but let’s leave that out of the conversation, since it doesn’t affect the topic.
Good luck getting a decentralised network accepted as a trust service provider if it’s not even fully embraced as a social network… Who’s going to promote it as a TSP to governments? Who’s going to use it apart from the 3 guys that wrote the NIP?
And that brings us to the other aspect of it. How do you expect that to work, if Nostr fails as a social network and most of the relays die with it? Who’s gonna sign your legal documents then?
Again… fantasies…
Now don’t get me wrong, creativity is always awesome and we shouldn’t let it die away. It’s also very fun and exciting to have at it with ideas such as this one. But that’s the thing. They’ll end up being just that. Ideas.