I agree with this take. My one concern is it has the potential to diminish the entire brand. Even with giant warnings about losing warranty/support when installing 3rd party app stores or side loading apps, at the end of the day the back of the phone has a big Apple logo on it. So when the customer fucks it up and Apple refuses to fix it, they’ll still blame Apple.
I think plenty of software development companies quite like to keep that 30% to themselves. I could imagine Microsoft, Adobe and others refusing to ship their software on the app store at all if using their own store let them keep more of the purchase price.
Apple's hardware house of cards might come down if developers are allowed to push the devices past what Apple allows due to form-over-function design decisions they make, and I'm okay with that.