TVLand, WGN, FS2 are just 3 of them... They are in HD on the spectrum tv app (which has a horrible framerate) but in blurry SD on my DVR. This is disappointing.
My guess is that its a bandwidth issue.
Each linear HD channel consumes much more bandwidth than a SD channel. Only so much of the coaxial pipe can be dedicated to linear video programming, with the rest dedicated to data / internet. Everytime Spectrum increases internet speeds, HD channels will go away. Only the most popular (highest rated) channels will be sent to homes in HD.
Only the most popular (highest rated) channels will be sent to homes in HD.
...or more and more HD channels will be converted to switched digital video.