Charles, your attitude is the perfect illustration of the problem.
The terms? Have those been codified into law at some point? They don't mean anything until a judge says they do. If Apple put in the EULA that they reserve the right to break into your house at night and trash the place and take your stuff, do you think if they actually did it, a judge would just say "Well, he agreed to it, I guess it's fine," and dismiss the case against them?
Obviously there's a line, and it's not "whatever Apple says." It's not "whatever Microsoft says." Even in the US, where the IP courts seem to be the enforcement division of every large corporation ever, there's a limit to what they can stick in the EULA and have it taken seriously. The more they push it, the more likely it is that someday someone will push back successfully. Ideally, the shrink-wrap license as a whole would be scrapped... dare to dream.
Besides all that, I wasn't talking about what Apple could legally get away with. Did you see me suggest that Apple should be punished by the government for violating a person's rights to control their own hardware? No? Then the terms and conditions aren't pertinent. People keep bringing them up as if they are the very definition of wrong and right. They're not. I'm talking about ethics, not what the corporatocratic government thinks is fine and dandy. I'm talking about what is "understandable."
When I buy something, it's mine. I can buy a Toyota Corolla, and it's mine. I can do whatever I want to it... paint it with a paint roller, take the doors off, drill holes in it, break the glass, thoroughly destroy it if I wish. I may not be allowed to drive it on the road, but I'm not harming Toyota in doing so, and they have no claim against me for any of it. It was my car to do with as I please, after all, even if all of the patents and trademarks still belong to Toyota.
If it's my car, does that mean I own "the Toyota Corolla?" No, I own A Toyota Corolla. HUGE difference. If I own THE Corolla, that means I have the full rights to the trademarks and various patents involved in the vehicle's design. I would be fully within my rights to start building them on an assembly line and selling them.
I don't have that right, though, just because I bought a car. I own my particular copy of the Corolla, and I may do anything I want with it as far as Toyota is concerned, but that's as far as it goes. I can't make them or collect royalties from those who do. I own one example of the item, not the intellectual property behind it.
Software would be no different if copyright laws made any sense. I may not be allowed to make my own copies of MacOS and sell them to anyone, but it doesn't mean that the copy running on MY machine by lawful means rightfully belongs to Apple. That's some made-up crap that should never have been allowed serious consideration. And again, that's the legal definition, and I wasn't talking about that.
So no, as I said, it's not understandable that Apple would want to control what happens on their platform, at least if you interpret "understandable" to mean reasonable and appropriate. It's understandable in the sense that Apple wants to eat their cake and have it too, but it's certainly not ethical in any sense of the word. If an OS doesn't recognize that its job is to serve me and me alone, it's not fit for purpose.