If the make sideloading high-friction, either via account-bound or apk upload or permissions from MNO/ISP, I will leave android. I have a bunch of my own apps that only I use, not released to the public, if I cannot use them, I have zero reason to stay on android.
I think one of the reasons they want to lockdown the system is to prevent guys like me from locking THEM out of my home/ecosystems, as and example, I build my own launchers, specifically for TCL TV's, which runs Android TV and has Developer Mode + adb. Which means I remove all the bloat & ad garbage, which they want to prevent.
We will get to the point where google will remove your ability to set custom dns servers and only use theirs.. just wait & see friends.
Anywhoo, when this side loading fence materializes, I will jump ship to apple.
Why jump to another abuser when you could seriously start looking into alternatives? Ubuntu Touch has a really active community and it's very stable, you can even emulate android apps which you might absolutely need.
I don't see Apple as the obvious next step; the obvious step, when one is pissed off with abuse of power is open source, not Apple.
Sideloading is already worse on iOS
Why to apple?
Yeah, as an iOS dev, the grass is not greener on this side of the fence…