I think we crossed the point where Linux is less shitty than Windows. KDE and XFCE can compete.

That could very well be, but less shitty is the wrong metric. Can get shit done is the right metric, regular users don't care about corporate telemetry and adware so long as it doesn't get in the way of getting their stuff done. A good example of what I mean is a work event I attended a year or two ago. We had a bunch of guys up on the stage and between the lot they probably had over a century of combined Linux experience. Still, it took them a good 10-15 minutes to get the projector working. Now imagine a regular user in that situation.

For some time I had a Linux NUC, so no monitor. When I had to give a presentation I’d set it up to boot straight into the slides. I thought that was pretty slick. I’d bring a keyboard for emergencies but didn’t need to plug it in, just a slide advancer. But it required preparing beforehand. Linux is the Batman of OSes. You can do anything, but it requires prep time.

Who says the windows or mac users would be any quicker, per-se? Some days the windows folks get lucky, sometimes the mac folks get lucky, and some days the Linux person might actually get done faster than everyone else (it has happened!).

If you need to use local hardware you haven't used before; it's always a good idea to arrive well in advance to get yourself set up. You never know what you might run in to.

How? I thought this was a solved problem. I've been using arandr for a decade.

Hard to guess, if someone doesn’t use many different setups they might just not be familiar with arandr.

> it took them a good 10-15 minutes to get the projector working.

I installed my old projector ages ago, on a 1st version PPC Mac Mini running Debian and the Freevo media player (if memory serves, Kodi didn't even exist as XBMC back then). No problems whatsoever setting up the whole thing, aside the atrociously loud BONNNG! the Mac Mini played when turned on, but that's another story. I think setting up hardware is a hit and miss, and sometimes crap happens also under Windows where drivers are packaged according to brand, not chipset, and often bring all sort of junk with them.

How disingenous, this comedic scenario is literally a mainstay at any tech conference

You're exactly right. Many normal users are "single issue voters" when it comes to OS choice. Linux could be the best operating system in the world, and Windows could be flaming trash that will drain your bank account and shoot your puppy, but if the user has an application that's important to them that runs on Windows but not Linux, they will always choose the "shoot my puppy" choice because at the end of the day they just want to ruin that application.