That's right, you non-patching bastard! The internet is filled with worms like blaster and nimda, and they will never go away because of idiots who don't patch against critical vulnerabilities.
Aside from patches that correctly fix legitimate vulnerabilities, Microsoft also has a history of releasing broken updates (and fixing them later when they've already done damage), removing features from their products, releasing "important" updates that are ads for future products, adding annoying new "features" to already-released OSes, and similar behaviors. They aren't the ones that I want as the ultimate gatekeeper of how my computer works.
Aside from that, I'm not going to use any OS that reboots itself without my specific instruction to do so. In terms of security, Windows 10 may be a net gain, taken globally, but at the individual level, it's a step backwards in some ways, and I'm not willing to take that step.
And anyhow, even if there were some legal issue with going against its "end of sales" statement, Microsoft could sell licenses for Windows 7 to a company that builds system images. That company would sell licensed images to another company, which would also buy PC hardware and image the drives themselves. It's not like Windows 7 licenses are completely unavailable, even now.
Aren't there ads on Slashdot
Only if you don't disable them...
and pretty much every other operating system like Android, iOS etc
The OSes themselves don't have ads, unless you count the various app stores. Although on Android, the Google Apps packages do some phone-home stuff, if that's what you're actually worried about. They aren't an essential part of the OS.
Steam fans are gamers who don't understand computer technology.
A subset understands, but doesn't care about the same things that you do. I pay rental-level prices for games that may disappear at some point, and which I need to be connected to Steam most of the time to play. They collect data on which games I play, how often, how long, etc. Frankly, I don't care that they know those things. It would suck if a portion of my game library suddenly disappeared because something happened at Valve, but I see that as part of the price, besides the $5-$10 per game that I've been paying for last year's blockbuster-level titles. It seems like a fair trade.
buying ad-free Solitaire for the five years that you plan to use the laptop. Or what am I missing?
Buying ad-free Solitaire won't fix any other system ads, user data collection, etc, that are the actual reason not to use the OS. Solitaire's basically completely beside the point; there are free versions of the game anyhow, so problems in Microsoft's version are moot. The info in this link ought to give you more of an idea of the security issues that a lot of people are talking about here.
why not use disk-encrypted Linux and put Windows in a VM for those one or two programs that are Windows-only?
Programs that require direct GPU access and as much of my system's RAM as possible are the top of my list of reasons for keeping a Windows partition around, personally. So, I've basically got one boot option to put my machine into gaming-console mode, and one to put it into everything-else mode. That set up will change when there's either a technical shift in what I can easily do on Linux or my interests change enough that I'm no longer interested in running that kind of program.
Why isn't there more consumer push-back?
Because it's not being reported in places that non-technical users read, and if it was, it wouldn't be worded in a way to make them understand and care about the implications....and if it was, there are a ton of people that don't care too much about their privacy anyhow. We'd hear a resounding "meh", rather than any kind of real PR backlash.
You double clicked on a game icon and it launched within two seconds
Well...either that, or you got a message saying that you needed to lower/raise the bit depth of your display, enable/disable some memory manager, or something similar. I kind of missed Windows 3.1 too, until I started playing with it in a VM and kept running into all the antiquated bits that I'd forgotten about...then it would make one of the classic "ding" sounds, and I'd forgive it in a wash of nostalgia.
You should be able to simultaneously run a remote desktop session or VNC on the Pi to control the UI in a relatively lag-free way, hit a key to start streaming, and enjoy the video. Of course, this whole set-up only makes sense if you don't have a smart tv, blu-ray player that supports streaming, etc. Otherwise, why not just use what you already have and set up network shares on the PC?