And watch European citizens complain that now their game consoles are more expensive because the console makers won’t sell them at a loss since they can’t be subsidized by fees.

Or since there is already a shortage, the console makers prioritize the US.

Then Apple will have a much higher fee to use their developer tools.

Also in the case of Google, you can’t use Google Services outside of the Google Play store. The only company that has had the resources to duplicate many of those services is Amazon.

In iOS users case, you won’t be able to use iCloud backup, the same notifications controls, access to global settings, probably no access to KeyChain or any other API that requires server side integration.