I've ran into that with one shitty vendor (I won't/can't give any details beyond this) lately. They 'support' deb-based distributions, but specially their postinst-scripts don't have any kind of testing/verification on the environment they're running in and it seems to find new and exiting ways to break every now and then. I'm experienced (or old) enough with Linux/Debian that I can go around the loopholes they've left behind, but in our company there's not too many others who have sufficient knowledge on how deb-packages work.

And they even either are dumb or play one when they claim that their packages work as advertised even after I sent them their postinst-scripts from the package, including explanations on why this and that breaks on a system which doesn't have graphical environment installed (among other things).

But that's absolutely fault on the vendor side, not Debian/Linux itself. But it happens.