Re: what about RPi?
Companies like Red Hat dropping 32 bit support isn't going to make your Raspberry Pi stop working. It will only make it impossible for you to run purchase paid support from Red Hat for it. Someone will probably still compile 32 bit versions of it, just like CentOS recompiles Red Hat. Someone else will probably backport security fixes to the last supported 32 bit version so you can continue to using that.
By the time those sources dry up, you won't be able to buy a Raspberry Pi with a 32 bit CPU.
Biting the hand that feeds IT
