I’m assuming this list was limited to American TV, because the best show ever made in the human history is Doctor Who.
Well Monty Python is there so, I think the US heavy list is an artifact of parochialism.
34-1! WTF
But in addition to eliminating quiz/game, reality, chat, variety, news shows, mini-series - I would also eliminate non-US origin shows to give the USA a chance, otherwise my list of 35 best would be loaded the other way (but not so heavily)
Otherwise: The Avengers, Prisoner, Callan, Dad's Army, Minder, The Onedin Line, Porridge, Robin of Sherwood, Fawlty Towers, 'Allo 'Allo, Black Adder, New Tricks are gonna knock US shows off the list.
And to assuage the feelings (which are important) of USA readers: Current running US shows that will probably make future Best Shows ever list
Battlestar Galactica, House, How I Met Your Mother, My Name is Earl, NCIS, Terminator: The Sarah Connor Chronicles