Effectively zero.
Disclosure: I work at Apple. And when I was at Google I was shocked by how many iPhones there were.
This is flabbergasting, how could such a large proportion of highly technical people willingly subject themselves to being shackled by iOS? They just happily put up with having one choice of browser, (outside Europe) no third party app stores, and being locked into the Apple ecosystem? I can't think of a single reason I would ever switch from an S22-25+U to an iPhone. I only went from 22U to 25U because my old one got smashed, otherwise the 22U would still be perfectly fine.
That doesn’t surprise me at all haha appreciate someone a little closer to the question answering it! I know it still counts anecdotal but I’ll take it