I wouldn't be surprised if a heavy duty Mac Pro-class ARM chip from Apple looks like AMD's Epyc, with an array of smaller 5-7nm ARM cores surrounding a larger 1

I wouldn't be surprised if a heavy duty Mac Pro-class ARM chip from Apple looks like AMD's Epyc, with an array of smaller 5-7nm ARM cores surrounding a larger 12-14nm bus core. Apple and AMD both use TSMC and this fab technology is apparently ready for prime time. It would also make sense from a manufacturing standpoint to use a slightly modified phone core in parallel for their poweruser desktop refreshes rather than design a significantly different CPU (otoh Apple seems to have no problem leaving the Mac Pro to languish for years at a time). They might even get better yields by fabbing a single core with both shared-MMU and the phone SoC features and then disabling one or the other if there are defects.