[shaabanban]

You could make the argument that they've made at least a partial transition since the 2008 64 bit UEFI with the whole T2 ARM co-processor thing.

[chipotle_coyote]

Mac software the way the original author is talking about it is still basically running like 64-bit Intel Mac software, though, right? Catalina is a transition of sorts in that it's dropping all 32-bit compatibility, so that could be a footnote, but I think that's about it -- until-slash-if Macs make the oft-rumored transition to Apple-designed ARM CPUs.