I'm fairly certain there is only one platform version for PC(Windows/Mac). It doesn't matter what version you buy or on what machine; the mac version is the PC version and the Windows version is the PC version. Basically it's just "PC platform." So whatever you buy for the PC platform you can use it on either Mac or PC. The only time i've ever seen a company discern between the two is when Activision tried to squeeze as much money out of Call of Duty as possible when they released the Mac version of Call of Duty: Black Ops.
Also, I think you should stick to coding and stay away from trying to predict market trends. As is the Mac isn't growing by much if at all. Windows is still, as a whole, 90% of the market share.
https://www.netmarketshare.com/oper...=9&qpcustomb=0&qpsp=176&qpnp=24&qptimeframe=M Both Mac and Windows have pretty much dug in for the last five years with Window's highest market share at 91% in 2009. According to the stats linked Mac has actually lost .01 of the market share since 2013. Then you have to consider how Mac actually rose from 5% pre-2009 to it's current 7%: It's immense success in the smartphone market. Given it's almost been 10 years I sincerely doubt we'll see any big change in market share especially in way of Mac overcoming any huge hurdles. Apple's Mac would be lucky to break 10% by 2018 at this rate if the OS even holds any relevance by that time besides the same audience it's always had; that being a very, very niche group which mostly consists of the stereotypical hipster crowd only spurn on by iOS which, as you should be aware, has lost a significant share in it's own market since 2010. iOS only now garners 41% of the mobile OS market share which is a far cry from what it was and a steep drop from it's rival, Android.
Point is, everyone is losing interest in Apple products. The golden age of Apple died with Steve Jobs(May he rest in peace). Right now Apple is all about holding onto what it's already got. The "
iGeneration" has come and gone, you're two years too late to make such blind statements as to the relevance of OSX and the fate of Windows.