I don't think you can just do anything you want in the name of security and protecting users. This will make installing apps needlesly difficult. There is already a warning when enabling installation of apps from unknown sources. That should be enough. If users don't read that's on them.
The real problem here is not that Google is doing this bad thing. The real problem is that they can do this bad thing. They shouldn't have this power. Something needs to be done to rain in Google and take back Android as an open platform.
The real problem here is not that Google is doing this bad thing. The real problem is that they can do this bad thing. They shouldn't have this power. Something needs to be done to rain in Google and take back Android as an open platform.