Google has changed the game on something you already own. I'm sure their lawyers have done their homework, but in some jurisdictions this is certainly actionable.
None of the other platform vendors with totally closed platforms are paying out anything.
So with even a room temperature business IQ, it's pretty clear that closed platforms are the best way to do business, and court rulings in both the US and EU have affirmed this multiple times over the last decade.
People here are complaining about a separate thing, which is that the process for installing an app outside a blessed way is changing, becoming harder for the first such installation and easier for subsequent installations on new devices.