Just let them advertise they can sign up on their page (not a direct link).
Apple is shifting more and more of revenue expectations on services and this makes them compete against the app developers that helped prop their platform HW sales so far.
The competition is not even as Apple also makes the complex and unevenly applied Review rules which this is just a public face of (up to the personal reviewer and review board interpretation and there are rules they throw at you that are sometimes just very loosely related to the language there):
https://developer.apple.com/app-store/review/guidelines/
The fun of being told that if you do A then your app cannot look “store like” in terms of UI is perhaps hard to appreciate (and seeing some competitors sneaking through without any changes even better). Recommendations to users? Store like. Big image tiles? Store like. Carousels and categories/sections? Store like. Curiously you can see this starting to happen when Apple Arcade entered the scene…
. They are full of such rules, but people want their devices too badly so they are mostly always against the devs and pro platform maker so they have 0 incentive to change.