Obviously Color TV and all of the subsequent improvements was an effort (scam?) to sell new equipment.
All of these enhancements have improved picture quality, though I'm not sure how much they have improved the TV viewing experience.
Particulary in dramatic presentations, the content of the production is (IMHO) the key factor. This is why live theater has remained popular even without exotic special effects and realistic sets. When you are emersed in the drama, you accept the suggestion a prop . It's realism doesn't mater.
Unfortunately the content of most TV programing hasn't improved and has by far in large deteriorated , even movies are increasingly featuring special effects and ignoring the quality of the screenplay.
As you might have guessed, the advent of 3D TV doesn't send chills up my spine.