Microsoft's popular Windows 7 and the not so popular Windows 8.1 operating systems are one step closer to fading into oblivion. OEMs now will not be able to sell PCs with these older OSes pre-installed.
This means that now on buyers will be able to procure new computers running only Windows 10. However, if you prefer Windows 7 to Windows 10, there is a way out. While you can still opt to purchase Windows 7 Professional pre-installed PCs, these units are likely to be old/existing stocks that OEMs would desperately try to get rid of. Do remember that Windows 7 is currently in the Microsoft Extended Support period and will continue to be officially supported only till January 14 2020.
Also, it is worth noting that Windows 7 Professional was taken off retail stores and has been unavailable since October 31 2013. Windows 8.1 continued for a little more than two years, and reached the end of retail sales stage on September 1 2015.