Google says "power users" can "still install" unverified apps. Here's what that actually looks like:
Delve into System Settings, find About Phone
Tap the build number seven times to enable Developer Mode
Dismiss scare screens about coercion
Enter your PIN
Restart the device
Wait 24 hours
Come back, dismiss more scare screens
Pick "allow temporarily" (7 days) or "allow indefinitely"
Confirm, again, that you understand "the risks"
Nine steps. A mandatory 24-hour cooling-off period. For installing software on a device you own.
Worse: this flow runs entirely through Google Play Services, not the Android OS. Google can change it, tighten it, or kill it at any time, with no OS update required and no consent needed.