The Linux kernel is a separate system layer here, it's the AOSP parts like the Dalvik Runtime (equivalent of JRE) and components built on top of it (such as Play Store) which are being subject to permissive licensing abuse. If AOSP itself was GPL licensed, it'd have been difficult for Google to create something closed like Play Store as it'd have been considered derivative work.

You're right that broadly speaking, there is very little that could be done to stop this but having a culture of "everything GPL" in an organization definitely helps. For example, Sun was farsighted enough, though they couldn't stop Oracle from acquiring MySql, Oracle was still forced to keep MySql under GPL and they were able to salvage MariaDB too.

Similar was the case with Java. Oracle tried everything in its power to control its use and direction including legal means, it's only thanks to GPL that alternative implementations like OpenJDK and Amazon Corretto still exist. We can't even imagine the state of these software today if Sun hadn't licensed them under GPL originally but used some other permissive license instead!

Dalvik was used up until Android 4.4. Since Android 5 Lollipop the Java Runtime Environment is called the 'Android Runtime' or just ART.

https://en.wikipedia.org/wiki/Android_Runtime

https://en.wikipedia.org/wiki/Dalvik_(software)

Java and MySQL were already out in the open as open source projects when Oracle acquired Sun though.

I don't know much about Android's history but if Dalvik was created exclusively by Google and they had no intention of open sourcing it fully... it'd be akin to a closed source Java app on top of the open source OpenJDK... which would be allowed.

Not that it would help in this particular scenario, but Linux did not embrace the GPL development from about 20 years ago.

But they are!!