I think having two app stores being installed would (or should) satisfy this. I think the intention is to prevent Apple saying "either you use our store exclus

I think having two app stores being installed would (or should) satisfy this. I think the intention is to prevent Apple saying "either you use our store exclusively, or you opt out of all our apps". Google lets you install a browser from one store, a game from another, and everything else from the official Play Store. Google could also easily implement category switching. The URL navigation structure of android could just append ?cat=gaming.