Neat. Any "sand box" architecture, limits what you can run on that OS, because out of necessity or stupidity, some apps reach down below the OS library code or even to the actual hardware. Some things will run, others won't. Why have a second OS, unless you need to run an app not available in Windows? So what app are you needing to run that only runs in OS X?
This all gets very meta, if you start using cloud storage and cloud apps, then the OS on your own box becomes less and less relevant. An OS was invented, so that programmers didn't have to deal with the nasty hardware (and variations of that between boxes). But every solution brings its own problems over time. The OS became a "rentier" tool to ring fence users and forcing them to pay monopoly money for apps, that were non-portable between OS systems.
Game developers are the worst at using custom utility libraries (loaded as part of the game) or talking directly to the hardware. This is because game performance is the hardest environment to get good performance, particularly in the video.