Steam Deck

Yeah... I wouldn't trust ltt with much of anything at this point, especially especially when they're "speculating" on something. Imo ltt is now "tech top gear" except nowhere near as funny. You watch it to be entertained, not because you're going to get good reviews for stuff.

Yea seriously, after explicitly not addressing the workplace harassment, and still not making sure their data is accurate, Linus can go get bent

The biggest metric is, by far, panel uniformity: boot up a grey (#A1A1A1) image and you'll see how subpixels misbehave greatly, with a lot of extra green activity creating almost a "snow" or "digital noise" to the image. If you reduce panel brightness to around 35% and move around in a dark scene in a game, the fixed points of extra green actually become distracting once you know about them. You can also find little pockets with bad brightness or otherwise weird artifacts all around.

Still in the panel uniformity category, the Switch OLED panel struggles with horizontal uniformity, it's extremely common for the left side of the screen to have a different white point to the right side, and by a great margin.

Nintendo also doesn't calibrate panels individually at the factory, they load a "default interpolation curve" for brightness that means in all units I tested colors only look correct at 100%, 50% and 25% brightness. If you deviate from that, the screen keeps flip-flopping between too much green and too little green. If you test this in a dark room and with small increments of the brightness slider, you'll be shocked at how bad it actually is.

Not as noticeable, but still relevant, is the fact that if you have a portion of the screen with an absolute black element, everything in that vertical space will get around ~5% darker. For instance, if you go to the main menu in the dark mode and move your cursor to a game with a mostly black icon, and pay attention to the colors right above it, you'll see that entire section of the display being darker.

There are things it does quite well compared to earlier OLED panels though, like black to color transitions and having an actual RGB subpixel layout. Still, even a mid range phone from 4 years ago will offer better quality than this panel. But keep in mind, I'm only talking about the Switch - I naturally do not have a Steam Deck OLED to compare.