By this logic Apple is a monopoly in the mobile space since nobody can afford to ignore them when building apps.
In any case, if you're making a social media app or other international app, an Android version is likely more important.
There is no such thing as international anti-trust. In this conversation the US market is the only thing that matters since we are talking about US law. Hence, android does not really matter much for revenue.
Even in the US, Apple does not have even close to a monopoly over Android, anyways. At best they have 50% of the marketshare.
[0] https://appleinsider.com/articles/19/07/03/apples-app-store-...
[0] https://www.mobilemarketer.com/news/survey-iphone-owners-spe...
And even if the trends did hold up internationally, and I really suspect they don't, Android would still be better for ads and subscriptions internationally due to nearly three times the market share, despite a bit more than half the disposable income.
People don't really buy iPhones as soon as they have money unless it is a status symbol in their culture, which it really is the more the country is Americanized/anglophone. I think that correlation holds up much better than GDP PPP. There is no real reason for money to predict iOS market share except for that.
The point I'm trying to make here is that people will use that figure (often without much thought) to justify giving Android users a sub-par experience - which only serves to reinforce it. I've worked for several companies that have given parity to iOS and Android, and one that did not. For the former we did not observe a disparity that large. YMMV by region and industry of course.
Would consumers be better served if app developers had to pay the Google tax, the Apple tax aaaaaand the Microsoft tax, the Samsung tax, the HTC tax, etc etc etc?
[0]: https://www.bbc.com/news/technology-45063002#:~:text=The%20d....
[1]: https://www.hbsslaw.com/uploads/case_downloads/apple-dev/201...