Linux

There are a lot of factors I think.

Some are pretty legitimate, like the lack of Adobe or Autodesk support on Linux, which means a lot of people just 100% cannot participate in their industry using Linux. It's borderline illegal to use Linux if you're a mechanical or civil engineer; Solidworks and MATLAB are pretty much regulatory requirements; you'd probably lose your engineering license if you turned in a drawing made in FreeCAD. In the art space, tell a publishers you drew something in Inkscape and watch their personality leak out their ears. Everyone hates Adobe, but glory to Adobe.

There are also legitimate culture shocks; there's this LTT video where they had iJustine on, and Linus and Justine swapped platforms, he on a Mac, she on a PC, and they were given basic tasks like "install Slack. Take a screenshot. Paste that screenshot in a Word Processing document. Save it as a PDF. Send that PDF to James in a Slack message. Uninstall Slack." Justine immediately started looking around the back of the monitor for USB ports, rapidly found that a fresh install of vanilla Windows doesn't (or didn't at the time) come with a word processor that could save documents as a PDF, Linus immediately went to the web browser instead of the app store...They did similar stunts with their Linux challenge later on, though I'd kinda argue about the tasks they were set to do (such as "sign" a document, which Linus started to do cryptologically but didn't have any keys enrolled because who the fuck does, and Luke just...copy/pasted an image of his handwriting?) But anyway. Linux is different than Windows to use, and even a VERY windows-like DE like Cinnamon is going to have differences that will feel foreign. I remember tripping over "shortcuts" being "links or launchers depending on what you want to do."

There's also the fact that Microsoft has done a world class job at making the average normie hate and fear the command line interface. Because universally, when you see a cmd prompt appear in Windows, it is a bad thing. That hate gets transferred to Linux, where we do routinely use the terminal because while it can be a little arcane, with a little bit of learning you can do some powerful stuff. But, because people have been so conditioned to hate the CLI by Microsoft, you get exchanges like this:

"Hey I'm trying out Pop!_OS because you nerds keep saying it's good, and my laptop can connect to the internet with ethernet but not Wi-Fi, what's up with that?" "Well let's see, could you open a terminal and type sudo lshw -C network, and then copy-paste what it says here for me to look at?" "NO!!!11!! NEVAR!!!! How DARE you suggest I use a computer by doing anything other than pointing at little pictures?! The indignity! It's current year!!"

Finally, before I hit the character limit for this post, there's just a reputation around Linux. I've had this happen more than once, someone will ask to use my computer to look something up on the internet. "Sure." They find the Firefox icon on the quicklaunch bar just fine, it pops open, they're doing fine, then they notice the color scheme and icons are a little different and they ask "uhh, what version of Windows is this?" And I say "It's Linux Mint." And they lift their hands off the keyboard with the same gesture as if I just told them my cute furry pet in their lap is actually a tarantula. They have it in their head that Linux is deliberately hard to use because it's for computer nerds--they think all Linux is Suckless--and because they're not computer nerds, they can't use Linux. So the second they know it's Linux, they "can't" use it.