Because it’s not Windows and it’s not MacOS. Yes, it’s an operating system, but what people are comparing against are their expectations. I dont expect a program that’s not written or designed for my particular distribution or operating system to work. Now, in some cases it turns out that it does and sometimes it works better then under Microsoft, but that shouldn’t be your expectation. The software that is made for it runs as expected.

Working hardware is usually step one. If your hardware isn’t supported then of course you’re in for a rough ride.