Why are there no tube televisions anymore?

Why no tube TV's? Cost, reliability, resource usage and a hundred other reasons.

I have one that is almost 40 years old. Picture and sound are still functioning like the day it was new. I wonder if my LED sets will still be functioning in another 40 years.
Unfortunately, I won't be here to find out.
But, I have to admit that a lot of people like "dinosaurs". Especially our children. By the time they are my age I can only imagine what marvels they will experience. Perhaps some of them will keep tech from our present time, in their "dinosaur collection". (assuming they are still working)

My take on this is a bit different, not about the tech but maybe applicable nonetheless.   Recently had to change provider and cable vs streaming etc.  Lots of different qualities to be seen across offerings.  Sure i/we watch them all and complain but we still watch.  Why?  Because we want the answer or conclusion to the (previously unseen) episode or event.  We simply put up with it in order to reach the end.  

No so with music.  We've heard it a multitude of times (usually) so it's purely for the enjoyment.  Wouldn't put up with inferior as long as we have the proper equipment.  Watching TV we are prone to overlook quality to achieve the goal or the end.  Do you watch a football game or Yellowstone to marvel at the image? Now on a HT blog, this might not describe the average reader.  I wouldn't know.  

I’ve made a good chunk of my living as a commercial film director. As the poster above mentioned we had 550k color suites and 150k avid machines that became obsolete overnight. BTW, Those loans sucked.

My theory is that my high end Sony TVs are just about to catch up to my old Panasonic plasma in showing “directors intent”.

so much tv tech makes sports look better but movies look worse as 240hz exhausts me. 
If we all spent the time to go to tweak.tv and follow their instructions as a baseline the world would become a prettier place

while there seem to be far less intense discussions in the TV & video realm?

Different hobby.  Recreating pleasing sound/music is different from video interests.  The are many different preferences for audio sonics and many methods to achieve them.  TVs are resolution based so there is much less reasons for debate the end products-likely just which video resolves better.