I have configured Windows 10 on some new laptops, and it's OK - we're running either Chrome or FireFox for SM webmail. Some new laptops have been "retrofitted" with Windows 7, successfully. for a variety of reasons. I have avoided the so-called "upgrade" to Win10 on dozens of my clients' computers with great success. Only one desktop machine slipped through the cracks and is OK on Win10 after a "few dozen" tweaks, but I'm very happy for all those other computers to still be on Win7 (and a few on Win8).
In conclusion, "OK" isn't a great comment on what was supposed to be a revolutionary OS. IMO (and the opinion of many others) Windows 7 just runs better and is simpler to maintain. Extended support for Win7 "expires" in January 2020, beyond the typical 3-year life expectancy of even a new computer, but remember that we're still seeing some security patches come through even for expired Windows OS versions, and for other Microsoft products.