Is that allowed by app stores? Doesn’t it negate the walled gardens if you can effectively treat the app as a mini browser that executes arbitrary code ?
What app stores don't like is you reinventing javascript i.e shipping your own VM. What they don't mind is you reinventing html and css.
So it is common for servers today to send mobile apps
{"Elementtype": "bottom_sheet_34", "fg_color": "red",..., "actions": {"tap": "whatever"}, ... }
This is what the GP is talking about.
It covers a surprising number of usecases, especially since many actions can be simply represented using '<a href>' equivalents -- deeplinks. With lotties, even animations are now server controlled. However, more dynamic actions are still client-controlled and need app updates.
Additionally, any new initiative , think new feature, or think temporary page for say valentine's day, is all done with webviews. I'm not clued in on the review process for this.
Nevertheless, if your app is big enough then almost every rule above is waived for you and the review process is moot, since once you become popular the platform becomes your customer as much as you are theirs. For example, tiktok ships a VM and obfuscated bytecode for that VM to hinder reverse engineering (and of course, hide stuff)
Having one API for web and mobile sounds good but in practice often the different apps have different concerns.
And SEO and page speed were always reasons the server never died.
In fact, the trend is the opposite direction - the server sending the mobile apps their UIs. That way you can roll out new updates, features, and experiments without even deploying a new version.