It’s also because it’s a whole ecosystem. You’re talking about computers, people’s tv purchases, app purchases, migrating all their photos and documents…
And the fact that maybe they just like how iOS works better in general. People don’t usually buy a phone for one app.
This sucks, but I’m not going through all that, and using a phone I like less (and I’ve used recent Android phones) just for Nostr. I’ll find ways around it.