Same reason why Swan is not on Nostr. A relic of old culture where it is focused on NGU for fiat gains. They’ll both be left behind and forgotten eventually.
Discussion
Doesn’t have to be either or. Transitional postures are relevant to the whole ecosystem. Without overlap and bridges, Bitcoin is just an island of natives. Happy, free, echo-chamber natives. Many would have that. Many would have nostr the same. But for mass, it takes all kinds. No need to hate on the merchants between systems. Enjoy the liquidity they bring.