I think back also. The Dual standard black and white tv with its bowden cable operated swtiches for IFand timebase and the of course the need to make eht transformers that did not grumble too much at the two different frequencies and chuck out too much eht so the picture shrank. AC coupled videos so no blacks etc.
Not sure about the quality. Most of the early crt colour sets really needed a live in engineer, hence the rental market. Things were always burning up or just dying and the power consumption on many was high.
I can recall with fondness working in a factory making these sets and marvelling at over and over again it was the women who could do the best and fastest job of purity and convergence on them.It was seemingly black magic of some sort, as many of us blokes never managed to get them as good. Those times are of course long gone now. You ask how do modern tvs work. Basically modern tvs are really just computers running software with integrated parts like software defined receivers decoding chips and software to configure it all. Indeed I believe a lot of tvs these days use a modified version of the Android phone operating system. One annoyance these days, particularly with older people is that they take a long time to get themselves up and running. We of course, used to good old valves marvelled at the early transistor tvs coming on almost instantly, but now they can take up to a minute, and people are impatient with them and screw things up by jabbing remot buttons inappropriately and the saying the tv does not work. Toshiba are a particular problem as they also use wireless tech for the remote so it works from the next room and people now have so many remotes for so many things they tend to use the wrong one and all sorts of things happen! LCD and other flat screens tend to be of several types The basic lcd screen is a multi layer lcd, that works a bit like a Polaroid filter so light cannot get through it if its polarisation is opposite to a fixed one. However you need several for the colours and of course some form of back light. There are lots of variations on this theme, and now of course they are starting to use leds themselves as pixels too, not just as backlights. Viewing angle can be an issue when you are dealing with polarised light of course, but the clever trouser types seem to be doing very well at mitigating this problem now. Most of the driving of such displays is done on a matrix of horizontal and vertical address lines but a chip handles all of this stuff for you and also the correction of the very non linear law of the display.
I could write an essay on all of this stuff and be accused of over simplifying, so if you really want to know there are lots of technical books around that will probably send you to the funny farm. good luck Oh and one tradition of tvs has not changed. They all still have crap sounds speakers in them.
Brian