To a point I agree. But not back that far.
The languages/programming systems these 20yr old apps are using are no longer supported, haven't been for years. This is one area where Microsoft are one of the most generous, offering 10yrs of support for a product from release. If the programming systems aren't supported, how on earth can a developer truely provide support. Simple answer, you can't. And then there is the sticky issue of security problems...
I am racking my brains trying to think of DOS based apps (not Windows Console based apps), and I'm struggling. I know there is a common one used by Chinese Restuarants. A few years ago, a lot of EPoS stuff was DOS based, but these are all without fail Win32 apps now.
I applaud MS for having the balls to remove support for stuff - I know they got a lot of flack over NT4's demise - but at least they don't do what a lot of other companies do, not mentioning Borland (good ridance) - claiming to support a version, but when you call them, the only answer is you need to upgrade!
The above is true for mainstream applications but at the fringes things move a bit slower.
We recently had to support some customers using an old DOS based platform for testing GSM base stations. The box is totally obsolete but there is nothing else on the market that will do the testing they require. It's based on a DOS PC but there are no issues with software support. It doesn't connect to anything so security is a non-issue. It's unlikely that we'll find a bug in DOS or the development environment (Borland C++ - Sorry

) that will be a show-stopper at this stage - so manufacturer support for those is not an issue. It's no problem to support (a breath of fresh air compared to Windows based stuff, in some respects).
The problem is hardware support - which reminds me - anyone know of a source of 486 Motherboards?

In most respects Windows (currently 2K) was a monumentally bad choice for the successor to that box IMHO. If the users can get it into the building under the radar of the IT police it's fine, but as soon as someone figures out it's a PC internally and starts altering security policies, installing antivirus software, etc. the problems start...
A substantial amount of development effort does into continually migrating it from one version of Dev Studio to the next too. That disappears into the noise for a huge volume app with lots of manpower being poured into it generally, but for something a little more specialised it's a real pain.
Had it been based on something the end user barely recognises as a computer I suspect it'd have been much easier.
Kevin