People are here on Nostr because they want to try something new & different (most of them use multiple clients to try different features). My guess is similar to that when they had an alternative to gm, they switched. Also, "pv" feels like defining a moment in time, when Nostr started to find it's legs.

The good thing is you can wish people GM/ Hello and they'd still wish back. I don't use pv or even zaps, but I've found people on here still welcoming. Maybe your experience is different