According to Apple’s website, the computers eligible for the update include all MacBook laptops from 2015 and newer. It will also cover all MacBook Air models released in 2012 or later, all MacBook Pros released in 2012 or later, and Mac Mini computers released in 2012 or later. It will also cover Apple’s iMac computers from 2012 or later, the iMac Pro from 2017 or later, and the Mac Pro computers from 2013 or later.
As you can see, this is quite an exhaustive list, where the oldest computers that Apple will support date back to 7 years ago. This is good news for Mac computer users who are still holding onto their machines with no immediate plans to change them, but would like to get some new software features all the same.
This list is also more exhaustive compared to the iPhone and iOS 13, where it seems that Apple has ditched support for the iPhone 6 and 6 Plus, choosing to focus on the iPhone 6s series and later models.