Google isn't doing that out of the goodness of their heart though, having a robust app ecosystem is essential and they're doing it for their own benefit. I think there's a strong case that it's a big part of the reason iOS and Android ended up winning against the fairly large number of competing phone operating systems.

So while it's true that there is a financial cost to Google for hosting your app, there's also a financial gain in the sense that the presence of your app contributes to the popularity/viability of their platform.

I don’t know how the “goodness of their heart” is relevant, but I think you’ve just arrived at the concept of a business: revenue, expenses and profit.

The point is that the issue is often framed as "ungrateful developers" taking advantage of the infrastructure Google provides when in reality developers making use of Google's infrastructure provides value to Google in itself.

Aren't apps like Spotify and Netflix the ones where you don't pay through the app but bypass the store? That is, the ones that cost the most don't pay much to Google and Apple but the small developers who can't fight back and rely on the money have no choice.

Apparently these apps have to integrate their billing systems with Google Play by September.

https://android-developers.googleblog.com/2020/09/listening-...

Wait and see