I don't think it's particularly hard to see the distinction between "do whatever you feel like, but someone will write down that you did" and "no, you can't do that. You'll do what we tell you to do".

And if "do whatever you feel like, but someone will write down that you did" is too much, one can readily install a GNU/Linux distro on a Surface. You very likely won't be able to do the same on any iOS device, even the iPad "Pro".

The set of things the MS records is much broader than the set of things Apple bans.