I'm not happy with this. I waited on XP until they got over vista, and I'm still on 7 while I watch in bemusement at the windows 8.1 nonsense. Now, with windows 10, my security updates will come bundled with my unwanted OS changes. I doubt microsoft will let people opt out of unwanted cloud-based security risks or crazy interface experiments.
Had this experience with Mac OS X. For 10.4 they switched to a new, dynamically linked libstdc++ that used the new Itanium C++ ABI. 10.3 had a statically linked libstdc++ and the old ABI.
They pushed out an OS update that installed the new libstdc++ on 10.3, breaking linking against libstdc++ with standard cxxflags. You see they had integrated cross-compilation for 10.3 into the new Xcode on 10.4, and didn't give a shit about people who were still compiling stuff on 10.3.
I decided after that that if Apple was going to break working compilation on my OS because I hadn't upgraded to the newest and shiniest, then they didn't really want my money. They seem to be doing OK without it, and I'm doing fine without them.
If Microsoft pulls this sort of stunt with Windows, then fuck everything about this change. They're such sticklers in the opposite direction, doing so much to ensure backward-compatible everything that the house of cards sometimes comes crashing down, that I don't think that will be a problem with Windows 10+x.