For mobile and desktop, sure 32 bit is fading, but embedded 32 bit is so far from obsolete. I don't know how you can even claim that when even 8 bit platforms still have a huge market share.
ARM cortex-M (32 bit) has only recently been able to chip away at 8 bit platforms and gain major use
https://en.wikipedia.org/wiki/List_of_common_microcontroller...