This market became a “requirement” (which is a bit BS since Android ecosystem is still much larger than iOS, but anyhow...) because people voted for this system consistently over many years (again and again). They voted with their wallets for it when the iPhone was a tiny newborn dream and RIM/Nokia were king, they continued to vote for it year on year after Android was released, and they are still voting for it... as is.
With this in mind: It’s arguably also intellectually dishonest to pretend that we all woke up today in some kind of “iOS only world” and should now regulate it. a) It’s not, and b) you would be killing the very thing that made everyone want this ecosystem in the first place.
If all the “regulate them!” and “open the store!” people win, then history says most will eventually move on to a new ecosystem that works like the old one (which people evidently like). Android has been open the whole time and the money gravitates away from it... If highly regulated and fully open phones worked so well then iOS would be a footnote in history books, and not the powerhouse that you want to squash.