Education isn't really working at this global scale. It doesn't reach people the way you seem to belive it does. Many, if not most people are generally disinterested in learning new things and this gets amplified when it involves technology.
Nope. We could, for example, ask developers to register with their legal identity to release apps.
Play store can be fast and verification based and the F/OSS stores can be slower, reputation and review based.
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But fundamentally the easiest thing is to ask people to pay to unlock the phone's security barriers, this makes it harder and costlier for scammers.
Simple example: I have a foss VPN app running on my phone to avoid censorship and surveillance in some countries I visit. While using this app is no problem, non-anonymous development might carry consequences to the developer in some dictatorship jurisdictions (which are plenty of). I'm not sure all devs of such system would be willing to give their ids.
Another example is that this way US can cut out countries and people they don't like from mobile usage (which basically equals to modern social life). Look into sanctioned judges of international court because US protects war criminals.