On the surface, it may seem that macOS Mojave is an extremely minor update. Other than Dark Mode and the reliance on Metal graphics, it doesn’t seem a whole lot different when you look it over, as I did starting last month. But the mere fact of choosing Metal means that Macs without support for that graphics technology have been made obsolete.
Before Mojave was announced, I had planned (hoped) to test the betas on my 2010 17-inch MacBook Pro. Obviously that’s not possible, despite the fact that it has an SSD formatted with the APFS file system. That’s because its graphics hardware, state of the art eight years ago, preceded the arrival of Metal.
A 2012 MacBook Pro, where a Retina display debuted on Macs, works just fine. So do older Mac Pros with graphics cards that support Metal. So, my only option was the iMac. With a Fusion drive, it lost out on the APFS conversion last year, because Apple couldn’t make it compatible. It appeared on the early betas of High Sierra, but was soon pulled.