The question is then.. is a 2020 MBA admissible at this point? Let's go back to the founding liberation documents:
"Yes! Score! We should make a Mac army and go around liberating poor old 68k Macs!” from 2001-08-24.
So, at this time, Old-World PowerPC Macs were already obsolete. The initial link to the 68KMLA has PPC Macs not being allowed.
I think it's fair to allow Intel Macs now - obviously, since I've contributed a bit to it. I would argue that Core Solo and Core Duo are certainly allowed, since they're 32-bit only. In November 2001, Mac OS X 10.1 was out, so no <G3 could run it (unless upgraded). Mac OS 9.1 appeared in January 2001, which was the last one for pre-G3 Macs and Mac OS 9.2 appeared in July 2001 for ≥G3.
So, by the time the 68KMLA forums were launched, earliest PowerMacs at 7.5 years weren't allowed even though they couldn't run either the latest Classic Mac OS, nor Mac OS X.
Perhaps this gives a bit of guidance for Intel Mac cut-offs, though as a caveat I suspect we'll just include all Intel Macs from hereon. A few Intel Macs can still run Tahoe, but won't be able to run Mac OS 27.
So, although obviously there are ways to run newer macOS versions by hacking around, the following cut-offs for Macs that can run these OS's spring to mind:
| From | To | Mac OS X/macOS versions | Why |
|---|---|---|---|
| 2009-08.. | 2011-07 | 10.6.8 Snow Leopard | PPC apps via Rosetta |
| 2012-07 | 2015-08 | 10.8.5 Mountain Lion | Last 32-bit EFI. |
| 2019-10 | 2020-11 | 10.15.8 Catalina. | Last Intel-only macOS. |
Lo and behold, my newest Intel Mac can run Catalina - how convenient!
OTOH, as I write this I realise I'm getting bored with all my criteria. What seems rational at first glance ends up getting rather convoluted, because of all the overlap between supported Intel Mac models and OS's across a 15 year period. Even, in the end, the rationale for saying "Nope, we don't cover supporting a 2020 Intel MBA even though it might still be useful had Apple not knee-capped it at macOS 15.x" seems mean. As it happens, my wife has a 2020 Intel MBA i5 and so my blatant vested interests are laid bare ;-) .
