The phone makers don't care about specific the kernel used in Android. They care that they can access AOSP. AOSP could use other kernels and other licenses, it wouldn't impact Android's success or value at this point.

Go look at the kernel version in Android, even Android 7.0...kernel 3.10. We might be overestimating how important linux is to Android.

OEMs that produce devices end up doing non-free things writing checks to companies like Micorosft for intellectual property, so it isn't like AOSP delivers on the promise to let anyone make a phone, GPL kernel or not.

If Google actually follows through with this Fuchsia project, do you think OEMs will balk because the kernel isn't GPL'd? No one will care.

I have to admit that I'd like to see a respin of Android using the NetBSD kernel.