This version of macOS [10.15/10.14] cannot be installed on this computer
Some might see an error “This version of macOS 10.15.5 (Catalina) 10.14.6 (Mojave) cannot be installed on this computer” while downloading OS updates from the Mac app store. It happens because of the new hardware requirement for macOS versions after Mojave. Your Mac needs to be a Mid-2012…