Just as an example of something that happened to me just today: I wanted to connect 2 monitors to my linux Home PC: 1 in the Nvidia GPU HDMI and another one in the integrated Intel HDMI. It doesn't work out of the box, and it is apparently not possible, at least not without thinkering with the BIOS and some config files (and the main response returned by google https://forums.linuxmint.com/viewtopic.php?t=265946 doesn't work).

So yeah, I can imagine how people coming from windows might be frustrated with that.