No, it's starting at the wrong end and not in any relevant way provide an improvement.
Checking for an too old & vulnerable is where you start.
And then you can consider to maybe also block other stuff.
There is nothing inherently less secure about an rooted device.
Sure you can make it less secure if you install bad software, but you can also make it more secure.
Or you just need to lower the minimal screen brightness for accessibility reasons.
Your claiming it's ok to take the agency from people away to decide over a major part of their live (which sadly phones are today) because maybe they could act irresponsible and do something stupid.
But if we say that is ok, then we first need to start to ban cars, because you could drive into a wall with it, and knifes, also no way to have a bath tube you could drown yourself.
And yes that is sarcastic, but there is a big difference between something being "inherently insecure" (driving without belt) or by default is in no way less secure as long as you don't go actively out of your way to make it less secure (by e.g. disabling security protections).