Here the question become complex.

While it is true what you say, it is also true that they must give you an option to not accept the changes.
And if you do not accept the changes, then they cannot apply them.

Now, if we are talking about a service, then the normal result is that I, as consumer, have the option to terminate the contract without any additional fees even if expected. In this cases people normally accept the changes since most of the time is more a mess to change provider than the gain. It is not the optimal way in my opinion, but at least it have a logic: the new contract is this, you have 30 days to accept or refuse it and if you refuse it we have no contract. In my opinion the correct way should be “ok, no new contract, keep the old one with its goods and bad” but at least I have a choice if the new condition are really bad (for me of course)

On the other hand, when we talk about hardware it is debatable what you can do on a device that is my property and especially if I bought it with a given amount of working features.

And, BTW, here we have the concept of vexatious clauses, which are void by default even if I accept an EULA that has them.