Your analogy doesn't work here. Going to a restaurant is like using an app store. Installing apks is like cooking at home. Nothing stops you from cooking a meal that will get you sick.
Now imagine that every restaurant in your city is owned by one of two megacorporations and they really don't want you to have a microwave at home, let alone a stove. They expect that you will get all your food from them. This is where it's going with apps right now.
It works fine for the point that they were making.
Which is that the fact that restaurants have to certify for food safety training and pass regular inspection is perfectly reasonable, and allows those who aren't experts in those areas, or want to continually inspect kitchens to dine out in confidence & conveinience. (or at least vastly reduced risk).
There should be some equivalent, safe, experience in the technology space. Especially given how powerful a tool of liberation it is.
Of course, who controls that, and the ability to turn off those safeguards is important for many many other reasons and... also a question of liberty. And so I think it is a difficult conflict to resolve elegantly.