Microsoft built this mess for profit, and continue to profit off of taxpayers indefinitely as hobbled state institutions are forced to pay permanent support contracts for old OSes because the states themselves mandated they use this shit by law. I'd love to see how many campaign contributions MS made to representatives pushing laws standardizing on Word or other bullshit MS only tech in state institutions and even worse, in schools.
Public education is infested with Microsoft giving away / heavily subsidizing their locked in products so children are hooked on them for life, and nobody is outraged about it.
Hell, the whole war for the classroom from all parties involved is disgusting. Microsoft, Apple, and Google all push free access to their proprietary services and products to lock kids into their ecosystems. And while Google's platform, Chromebooks, are much more open than their competitors, they offset that by also having the ulterior motive of farming these kids for their big data research (not to say MS and Apple aren't doing it too, just saying Google is far from innocent here).
The whole intersection of state and software globally is a giant mess of corruption. There is way too much profit to be made off taxpayers money for anything close to good intentions to win the day.
I keep hearing it will be the Year Of The Linux Desktop and it keeps never happening. That's why. No need for any wacky conspiracy theories, for the average user who just wants their computer to be a tool to get work done, the choices are Windows or Mac, and for large organisations who want to centrally manage machines, the choice is... Windows.
And yet Chromebook and iPad sales are booming at the expense of the PC. My sample size is ~20 family members. Those with Chromebooks love them and those with Windows 8/10 despise them. From a support perspective, it's considerably less for Chromebooks vs multiple issues with malware on the Windows devices.
Caveat emptor, YMMV etc.
We only got rid of the VMS controlled CNC lathe a couple of years ago - it ran off a VAXstation something-or-the-other. A 2100, methinks.
Granted, these machines didn't pose much of a problem besides scarcity of spare parts - neither of them had any need for a network, anyway.
Some industries are still full of Unix boxes from the 90's RS/6000 vintage. I've heard oil and gas industry is pretty bad for this sort of stuff especially in industrial control systems.
Problems arise when some bright spark figures out that it would be much easier to collect data via a network, directly from $Expensive_Device - or when another bright spark in accounting figures one can do without spare parts; after all, OEMs are supposed to keep stock of spares, right? No. Not years - decades - after sending out the EoL notice.
As an aside, I probably have one of the largest concentrations of Motorola pSOS hardware in the world in my shed (that is, the office next door) - my employer used a LOT of pSOS kit in the nineties, and as the platform became obsolete, noone thought to preserve a supply of spare parts; I quite literally dumpster-dived to reclaim whatever I could which warehouse staff had been told to get rid of.
Still happens every now and then that a customer asks for pSOS thingies. I really should get myself a stuffed dodo to put on the shelf next to the Motorola boxes...
I just saw a system that used Java applets. Java applets are outdated so they rewrote it in ...drumroll... Flash.
I can imagine there are plenty of systems still on DOS.
What makes this harder is that people bought into a platform that doesn't given them access to the code they run. The business that originally created it isn't interested in supporting it further (well, they are, i.e., "Windows 10", but I presume that that's not acceptable to our hypothetical "vote with there [sic] feet" person), and I don't really see that the business should be forced to support it, either. (It's not like MS didn't support it for quite a while, and don't still offer a solution.)
Software evolves. Ideally we're finding more secure and better ways of doing stuff, and shedding the old stuff, though I acknowledge the debatability of that. I acknowledge that it's also unfortunate that UI changes, and bloat, often seem tightly coupled with that. But if people also persist in choosing non-free, non-open source software…
Of course, security vulnerabilities do still become more known over time, and if you patch for them, you end up rotting code.
To handle both code rot and security vulnerabilities, you need software that is persistently maintained and upgraded, which means having a software team permanently on the job instead of what a lot of government software came from: One-time projects where a contractor comes in and does something.