A honest implementation would have a "child/grandma" mode and let adults install/read/listen whatever political/porn or GPL shit they want. Make grandma mode the default , I am sure the marketing can make it sound cool and some competent engineers can implement it so grandma doesn't by mistake enter the adult mode.
This argument is extremely flawed.
Apps can do malicious things without or with little interaction. Apple in this case is enforcing a few policies that it couldn't with sideloading, like apps that want permissions they don't need in exchange for functioning.
Websites don't get automated access to anything of the sort.
I understand that we could say that native apps are more dangerous because iOS is fulled of bugs and zero days so you want daddy Apple to be able to "intimidate" bad developers with a review.
There used to be websites you just accessed and got your iPhone jailbroken via safari exploits.
So argument is not flawed, its spot on.