I always buy this argument....to the extent that the more powerful, dangerous capabilities are still allowed but locked behind some (one time) process that indicates you have a base level of knowledge and understanding. If you want to make it default safe for normies, fine, but let me turn my own device into the dangerous thing it is capable of being.
The version of the your view that we are actually getting is _incredibly_ paternalistic and condescending to the general populace. The kind of society that is capable of protecting everyone from every conceivable harm comes with the kinds of tradeoffs that no one, not even the people who actually need the protection, are going to want.
Sadly, your view isn't less paternalistic in reality. It effectively amounts to telling people who have better things to do than care about their personal IT security to just suck it up. Billions of smartphone users worldwide are in this position.
Look, I'm not saying that this outcome is ideal and I hate the idea of a single, almighty platform gatekeeper. But with the world being what it is right now, draconian device lockdowns of some kind are the best option that is immediately available.