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.