> Linux also dominates smartphones in the form of Android phones.
Not really.
See any Linux specific APIs on the NDK official APIs?
https://developer.android.com/ndk/guides/stable_apis
Android is a mix of Java and Kotlin based frameworks, ISO C and C++, POSIX subset and a couple of additional libraries.
Whatever kernel gets used is an implementation detail for Google and Android device makers.
Can be completely replaced in Android 12, and the eco-system would continue to work.
> Chrome OS is also linux, and it's market share is currently at around 6%.
Basically Android (already mentioned above) and Web stacks.
https://chromeos.dev/en/android-environment
https://chromeos.dev/en/web-environment
Ah, but it does expose Linux you say, https://chromeos.dev/en/linux
Indeed, except of the small detail that as shown on the Google IO talk, it is actually a design similar to WSL 2, running a second kernel on a hypervisor based environment.
The real kernel powering ChromeOS doesn't get exposed to userspace and can also be replaced at any time, if Google so desires.
In fact, in a near future Android and ChromeOS can be running on top of Fuchsia and most consumers wouldn't even notice.