Apple abandons macOS* updates after a computer is over 7 years old or so.
At that point Mint or similar distros are your primary option for running a secure OS on excellent but aging hardware.**
Sleep/wake, battery management, and trackpad don’t work quite as well, and you usually have to install the Broadwell wifi driver manually, and the camera will be fussy, but otherwise it is the better OS for an old Mac.
* (no longer called OSX since they left v.10 behind a long time ago).
** you can force a later macOS onto older models, but it’s not very stable.
Apple abandons macOS* updates after a computer is over 7 years old or so.
At that point Mint or similar distros are your primary option for running a secure OS on excellent but aging hardware.**
Sleep/wake, battery management, and trackpad don’t work quite as well, and you usually have to install the Broadwell wifi driver manually, and the camera will be fussy, but otherwise it is the better OS for an old Mac.
* (no longer called OSX since they left v.10 behind a long time ago).
** you can force a later macOS onto older models, but it’s not very stable.