Why? Maybe they found out that somebody else have also been doing good job for the same cause and didn't wanted to waste their time to do dublicate work 🤔

I see new Nostr development and ideas popping up almost every day and people are still developing their own clients and relays even though we already have dozens of awesome of them! 

But of course everything would be faster if there were more economic incentives.

I think people forgets that we're still very early and developing open source protocols takes a lot of time.