Survivorship bias is a hell of a drug.
On the plus side, it makes fishing for the TONS of shows that never got past a couple airings surprisingly entertaining.
Crap was so ruthless seasons weren't fully ordered, written or filmed by the time they were on the air because shows would get cancelled overnight, so they were fully ramped up and working without knowing if they'd end the season they were doing at the time. Between that and how much cheaper everything was it's no wonder no film actors would be caught dead in a TV show until prestige television broke out of that mold.