Comment by judge2020

Because Apple decided that only software they approve of can be used on machines they sell unless the user explicitly allows software Apple hasn't accepted (via ctrl-click). On iOS, Apple decided that users can't allow untrusted software at all. Users still end up paying $400-$1400 for phones that run this software, so the 'free market' has decided that users want a software model like this (otherwise Android would be an even bigger player in the US than it is now).