It's worth deep diving into how analog composite broadcast television works, because you quickly realize just how insanely ambitious it was for 1930s engineers to have not only conceived, but perfected and shipped at consumer scale using only 1930s technologies.
Being old enough to have learned video engineering at the end of the analog days, it's kind of fun helping young engineers today wrap their brains around completely alien concepts, like "the image is never pixels" then "it's never digital" and "never quantized." Those who've been raised in a digital world learn to understand things from a fundamentally digital frame of reference. Even analog signals are often reasoned about as if their quantized form was their "true nature".
Interestingly, I suspect the converse would be equally true trying to explain digital television to a 1930s video engineer. They'd probably struggle similarly, always mentally remapping digital images to their "true" analog nature. The fundamental nature of their world was analog. Nothing was quantized. Even the idea "quanta" might be at the root of physics was newfangled, suspect and, even if true, of no practical use in engineering systems.
It's interesting how early digital video systems were influenced by the analog aspects. DVDs were very much still defined by NTSC/PAL even though the data is fully digital.
Yes agreed! And while it is not quantized as such there is an element of semi-digital protocol to it. The concept of "scanline" is quantized and there's "protocols" for indicating when a line ends, and a picture ends etc. that the receiver/send needs to agree on... and "colorbursts packets" for line, delay lines and all kinds of clever technique etc. so it is extremely complicated. Many things were necessary to overcome distortion and also to ensure backwards compatibility - first, how do you fit in the color so a monochrome TV can still show it? Later, how do you make it 16:9 and it can still show on a 4:3 TV (which it could!).