TLDR: Imagine a CRT/Osciloscope not sweeping row by row but instead line by line, where line doesn't necessarily mean horizontal but can be diagonal and even turn midway.
So, even if the display has pixels it doesn't matter, the interesting thing to eliminate is pixels in media (image/video).
TLDR: Imagine a CRT/Osciloscope not sweeping row by row but instead line by line, where line doesn't necessarily mean horizontal but can be diagonal and even turn midway.