Since its switch to the x86 machine architecture from PowerPC in the mid-2000s, Apple has been consistent with Intel as its sole supplier of CPUs for its Macbooks, iMac desktops, and Mac Pro workstations. The company's relationship with rival AMD has been limited to sourcing discrete GPUs. If pieces of code from a MacOS beta is anything to go buy, Apple could bite the AMD bullet very soon. References to several AMD processors were found in MacOS 10.15.4 Beta 1. These include the company's "Picasso," "Renoir," and "Van Gogh" APUs.
I'm surprised that Apple hasn't already. Not sure what ties them so closely to Intel, but imagine if the $6k Mac Pro was a 16 core machine (or maybe even a 32 core) -- people wouldn't be so quick to dismiss it.