This, from my perspective anyway, seems to be one of the biggest drivers of adoption for closed ecosystems. Users want to feel safe and not vet everything ( because it is hard to do well ) and it is genuinely hard to argue with that stance from a very pragmatic POV. As my friend once put it 'I don't want to spend my valuable time left fiddling'. For the argument you mention, I think I agree, because I still remember getting calls from family members, who installed something and now had constant unremovable popups everywhere.

That said, Apple seems to be more targeted now precisely ( compared to non-Apple linux and Windows ) because it has more people, who are lulled by the sense of security Apple curation model provides.

edit: I kinda get that the article is mostly about mobile devices, but the app-store concept appears to have moved to desktop world as well.