Whether or not I can install a different OS on a phone does guarantee an erosion of privacy. What you're arguing is that I should be fine with Apple because you can't install another OS. No thanks. And, yes, people do buy Pixel phones just because they can install a privacy respecting OS. Now, baseband is another problem, but - that's one that Apple has no claims to solve for either.
Yes, the vast majority of people don't install a custom OS onto their computers, either. So for the average person, this doesn't matter.
> What you're arguing is that I should be fine with Apple because you can't install another OS.
That wasn't my interpretation of the OP. The fact that it's possible, with a lot of effort, to get a privacy-centric device after the fact means nothing for the general public because they are never going to take those steps. So I think it's still reasonable to define "the market" as whatever the devices ship with.
It's great that we have the ability to install privacy-focused operating systems on some Android devices (I have one), but if I were to suggest this to any of my friends, they would laugh me out of the room. There is far less resistance recommending Apple products.
It's a victory if you want it, but utterly pyrric when both of the options on the "market" are useless for privacy.
Any legitimate competitors will follow the law in the jurisdictions it sells to, which is why this requires political solutions first.
