Yes, assuming that iOS's entitlement security has not been broken.
I have vivid memories of loads of relatives in the Windows XP era with browsers laden with toolbars that spy on everything they do and slow the computer to a crawl. Those users see something like the iPhone as a massive breath of fresh air. Nothing you install on the App Store can inject adware into the rest of the operating system like that.
That has literally fuck all to do with the app store. That's called sandboxing - the app store has nothing to do with sandboxing. They are different things.
Why are we being dishonest.