Because it's not about the operating system, but all the related services that are embedded in the browser.

I use chrome because it ties with my google account which ties in with... pretty much everything. It stores a lot of my passwords, it ties in with my gmail, my google workspace, my shared extensions that gets installed with any other chrome browsers through this google account, other google apps like google docs/calendar, and other google services like their speech-to-text, and it also ties in with my android phone that is linked to my google account.