I can mount my tablet and run Netflix. I don't think one needs to restrict what software I can install when it's already illegal to use it while driving.

Hell, I could pull a small grill into the 12V power supply and cook dinner while driving down the road.

The idea that software can police our lives is actually part of the issue we are talking about. Apple doesn't want us to be able to install arbitrary software on our phones "for our safety".