Because I am a believer in death of the author. That means that a developer doesn't get to decide what their game is or isn't about.
A dev could have put in a theme unintentionally. Does that mean you are not allowed to talk about it?
Why do they get to decide what a work of art means to me?
You can't update the kernel because your phone isn't running mainline Linux. The device manufacturers (which in this case mostly means chip manufactures) don't upstream their code. All the device specific kernel drivers are only in special device specific branches. You can get the code for the drivers (because GPL) and do the work to mailine it yourself. In fact that's what Postmarket OS does to get "proper Linux" running on phones.