Why has Pixar remained hesitant to produce series television? ...
Pixar doesn't really need to.
Because there's this other Disney subsidiary called Disney Television Animation that's producing series television.
Further, there's this other small screen division called Disney Toon Studios that's producing lwer burdget features and shorts. John Lasseter runs it.
Pixar can produce television series and specials any time the Mother Mouse so orders. Not really a problem. But since the Emryville outpost just closed its Vancouver studio, they'll have to do the teleivsion work in the bay area.
And (most likely) India or Asia.