If that's not what you're saying then your point is effectively moot, because if indeed Apple's platform control gets too egregious for some individuals then those people will switch at that point so there's no point in panic-switching now just in case.
In other words, users will switch when what Apple is offering does not meet what those users require. Some users will literally never care because all the software they use is signed and gatekept and so on; some users have jumped ship already because they want to be able to change whatever they want whenever they want. If things continue to "slippery slope" then more people will hit their own tipping point but asserting that it's going to happen all at once and apply to everyone is nonsense.
the point of boiling the frog is to make sure it happens slowly, such that the alternative options can no longer compete and be an option.
computer manufacturers and hardware makers cannot be trusted to make their platform open, because it would be detrimental to their bottom line. So it must come from regulation - right to repair etc, are on the right path, but what must be done is prevention of platform lockdowns. An owner of the hardware must be able to override all locks from the manufacturer.
We need an antitrust breakup of Apple. And Google.
These companies are rotten.
It remains easy to disable Gatekeeper if you want. New MacBooks still allow you to install other OSes, even though that would be trivial to lock down with signed boot requirements.
So far, none of the frog in boiling water predictions have actually come true at all. It’s just people parroting the same conspiracy every time the word Gatekeeper comes up, just like we went through every time Secure Boot came up.