Except Oracle did it first with SPARC ADI, Solaris on SPARC is one of the few UNIXes that have tamed C for couple of years now.

And actually pointer tagging architectures go all the way back to the early 1960's, with Burroughs being one of the first ones having a go at it.

It's not much of trailblazing if nobody follows on the trail.

Indeed, Apple is following the trail of Burroughs, iAPX 432, MPX, SPARC ADI, Lisp Machines, among others.