The costs of porting are relevant to value of the new audience. The value to the old audience is negative (what are we losing while they are focused in something else). The value to the team is complicated, has to be weighed, and big changes like new APIs or new revenue structures tip that balance.

It's relevant to whether the rates are based on competition, or to put it the other way, whether competition affects the rate they can charge.

If Google charged a lower rate, would it change the calculation for porting to iOS, so that Apple might have to lower their rate too? No, because you can't reach iOS customers via Google Play, so if you want to sell to them you still have to pay whatever Apple demands:

> If iOS was profitable before it still is, if it wasn't it still isn't.