You know I barely remember using a CRT TV for video games.
But onto the subject, that guy was pretty bad at super mario.
Definitely cool to watch the CRT refresh however, it's something people forget these days.
"motion pictures" and the movie theaters of yesterday were much the same.
It was kind of interesting to see the actual back lighting with the LCD. Samsung gets higher pixel contrast by splitting the screen into back-lit sections. Each section has it's own illumination control. So bright sections have a more light behind them than dark sections. This reduces the bleed through visible on the 4K display. The white LED's used for back lighting should be temperature controlled, cheap screens you will notice have a harsher blue glow about them. This is because the LED's used are "brighter" due to less color shifting using the phosphorescent materials in the white LED (white LEDs are actually blue LED's with red and green phosphorescent materials). You will notice this on the K value given on the LED 4K (color temperature) is actually considered very close to real white anything greater than 4200K will begin to be dominated by blue (white is a broad spectrum of colors), the LED manufactures give information of what numbers to order to get the correct color set for the LEDs (FYI it can get annoyingly technical most people don't bother so you get really crappy light like those cars with the LED headlights that hurt ones eyes).
These all are used to make a display function correctly (and not be blue saturated). Some manufacturers are now using RGB back lighting with mixing filters to blend the RGB output together instead of a white LED. Anyhow glad someone gave people an eye-full of what actually goes on in the display.
Also what he said about the display being updated all at once is only for most TFT type displays. They have cells that store charge in them (like DRAMS do) and that sets the value of the light valve in the TFT. The data is updated first then shifted to the storage cells almost all at once. It's not entirely true it's updated at once however, it's actually refreshed (like DRAM) a row at a time. The 'snapshot' happens all at once but the data going in is the same as it was with the CRT back in the day.