He is a developer from Brazil actually, and a Bitcoiner. So his Bitcoiner developer buddies were first to be informed about the protocol and pick it up and work on it; as a result the innitial community using Nostr are Bitcoiners, as well as decent Bitcoin integration. No idea what your perspective on Bitcoin is, but when i say 'Bitcoiner' i mean the people who stuck with it not so much for the purpose of getting rich but because they figured the world needed censorship resistant money for one reason or another, despite the rest of the world telling them that they were either fools or evil. Nostr is not much the different, welcome to the den of crazy cypherpunks.

https://cdn.nakamotoinstitute.org/docs/cypherpunk-manifesto.txt
- Eric Hughes 1993

https://bitcoin.org/bitcoin.pdf
- Satoshi Nakamoto 2008

https://fiatjaf.com/nostr.html
- Fiatjaf 2020