Except we aren't talking about the law. We are talking about corporations that sell you something and then retain control over it.

You have no say in the process, you have no representation. These are not rules that we as a society have determined to be in the best interests of all of us. These are unilateral decisions placed upon us. You have no recourse if you disagree other than don't use the thing.

Guns don't prevent you from doing anything. You still have the capability to do whatever you want with the thing. However, if you use it in a manner than harms someone else, in a way that we as a society have proposed, voted, and created laws prohibiting, then you deal with the consequences. But that is very different from having something in the gun that prevents it from taking ammo from another manufacturer. Or making it unable to shoot unless you pay a monthly fee.

Right, you can't break the law. Gun manufacturers are very explicitly not responsible if you break the law with one of the items they manufactured.

This is more like the gun manufacturer coming back two years after you bought it and preventing you from using bullets from a vendor they don't approve of.

If they couldn't, then they wouldn't, but they obviously can, because they do. This is not complicated.