We get why Apple limits their software and hardware to get users to be on the latest version, for example, iTunes 12.5.5 will sync with version iOS 10.2.1 and even previous version, u need to update from older versions though (if your still on 10.0, 9.3.5 or prior it won't sync with latest iTunes.) Same goes with software and what rums on the latest MacOS Sierra.. code changes allot of app packages I've used with WINE, I have converted Windows games, now all report as errors when trying to run them. in MacOS. so, probably an update on WINE ? However, shift the focus over to "compatibility" and what Mac systems will run MacOS, and suddenly that is the only caveat . Apple allows u to run MacOS far back as 2007. So if Apple cares about limited compatibility on pretty much everything else, why do they favor it with their OS's? Both iOS and MacOS? Is there any reasons for this ? I'm sure if Apple wanted to, they could limit the systems on running latest OS and iOS versions to two year old Mac's. Not that's a bad thing, coming from Apple.