[old_tv_nut]

Regarding picture quality:
Improvements in MPEG 2 encoders allowed visually artifact free HD pictures in about half the original bitrate, meaning that a broadcast channel could carry one very good HD signal and a smattering of lower quality subchannels. However, the old adage "content is king" is still true as it ever was, and broadcasters, cable TV providers, and satellite services all tend to press the limits of content over quality. "Content is king" dominated the development of home video recording, resulting in the reduced resolution but affordable VHS and Beta systems. It is no different with streaming services, where a lot of technical development is spent finding ways to squeeze the most content into the fewest bits with acceptable quality. The premier example of content over quality remains the huge number of bootlegged second and third generation "Star Wars" VHS tapes, which were used despite terrible quality.

Regarding resolution and interlace, there is no doubt that 1080P is superior to 720P, but the comparison of 1080I to 720P is dependent on the amount of motion. It was determined long ago by tests involving both non-expert and expert viewers that 1080I looked superior for most dramatic programs, but that 720P looked better for fast moving sports, basketball being a prime example. This difference has become less important with the advent of flat panel TVs that convert and present everything progressively (if the conversion is good).