UAC is a bad example - it's more like a walled garden where the wall consists entirely of gates, and when you approach any, it asks you if you want to open that. Hardly discreet.

In any case, this was in the context of app stores. What I meant is the ability to go flip a switch that enables sideloading, as you can do with Android or Win10 Store apps, if you know that one exists - on the assumption that if you do, you also know the risks. On Win10 specifically, this is stashed away in the system settings page titled "For developers", which comes with a bunch of warnings, so it's not something you can turn on by accident.

You just need that one person who thinks they are an “advanced user” to tell everyone else the secret trick and it spreads like a virus. About like all of the iOS users that aggressively quit apps because they think it increases battery life.

Or an app like Fortnite....

And yet this doesn't happen on Android.