I'd use iOS if they let me install whatever apps I wanted ("sideloading" as a term feels weird, as if they deign their users to load apps on the side, by their good graces. No, it's our hardware, we should be able to run whatever we want).

Android lets me do that, so I use it. No way I'd be without Vanced (rip) and other such apps. Android also has more interesting form factors, such as the folding phones, which Apple does not yet have.