Apple have used AMD as their exclusive dGPU manufacturer for over half a decade iirc, around the time the Mac pro dust bin launched, some modern iMac's have Vega based solutions I think, and iirc the R9 285(Earliest desktop revision of the later R9 380) technically launched first in MacBook Pro's, so there's some precedent for Apple being early adopters of AMD GPUs too. Oh, and VegaM is exclusively in Macs atm besides Intel's Hades Canyon G with VegaM chip.
I don't see them ditching Intel though, given they're entirely dependant on Intel's 5G modems to have any chance of 5G support in their mobile devices, gives they've burned all their bridges with Qualcomm, who has been essentially guaranteed to dominate the 5G space with their IP advantage for a while and have hardware in market much earlier. I can't see them switching from Intel chipsets in any of their electronics to be honest.