Windows is actually pretty reliable these days. In fact, a lot of its poor reputation stems from the old Windows 95 line which wasn't very stable or or buggy third party drivers. The question is (as long as you have powerful enough hardware) do you target an operating system used by billions with the resources of Microsoft behind it or the offering of some smaller company that can't respond to bugs as quickly.
Yeah, I'm well aware of how much better it is now than it was. Hell, I've been using PCs since they ran MS-DOS. Before that, the first time I had a computer on my desk at work, it ran CP/M.
I don't really disagree, it's just that it's still primarily designed as a desktop OS, and even my brand new Windows 11 laptop had a 'Blue Screen of Death' while I was setting it up, and I wasn't even doing anything non-standard on it (apart from tweaking the disk encryption in a way documented my Microsoft themselves, and it wasn't at that stage that it happened). It recovered with a single reboot, but nevertheless...
I'm also aware of how you can make software
very much more reliable using the methodologies and practices used in the nuclear, aerospace, and (to an extent) automotive industries. That is, where software is
safety critical and a bug can literally, directly kill people.
I'm not suggesting that it would be practical to develop every POS terminal to those standards, but we probably need to think more carefully about how things are developed and tested, depending on how critical the relevant systems are.
Apparently there is something that used to be called 'Embedded Windows' and is now 'Windows for IoT' that's designed for single dedicated devices, not sure if that was affected by this problem though. There is also a MS version called 'Azure Sphere', which is based on the Linux kernel. Again, not sure if this would be vulnerable.
It's also the case that Microsoft themselves sometimes completely fuck things up and don't offer proper solutions (as long as it's only a few customers who are affected). They did one update not so long ago (KB5034441) that changed the way the recovery partition was used, which meant that some machines didn't have enough space in their WinRE partition to install it (including my desktop), with only the helpful message "Error 0x80070643". All they offered was a powershell script (with hardly any instructions) or manual instructions to fix it using the command prompt. How many users even know these command line interfaces exist?
Using a big corporation isn't a guarantee of reliability.
Anyway, more of a few musings and a bit of a rant. As you were...