I’ll keep my 2012 Mac mini (which has served me well, never felt sluggish, and that I still love) on Mojave probably for the long haul because I need 32 bit support for the software that goes with my Apogee FireWire Duet. Glad Apple supports “old” versions of the MacOS with basic security updates for a few years. I think it’s three years, but I hope it’s more. Wish they would do similar with outdated versions of iOS. Pushing basic security updates should not be a problem for a company that is so big and has so many devices out there that are still in use that are not running to most current version of iOS.