Episodic versus serialized is irrelevant because there's no evidence that one is better at good stories and characters than the other?
Sneaking around detailed discussions of good for the moment, on the one side, episodic SF/F television has Star Trek, Twilight Zone and Outer Limits. And serialized SF/F has train wrecks like X-Files, Lost, BattleStar Galactica and DS9's Sisko in the fire caves and Red Eye Dukat. Well, it also has Babylon 5, but then, it is also widely hated as well as loved. It seems to me that it is precisely a concern with good stories and characters that would lead one to conclude that serialization, especially open-ended serialization (which would leave out Babylon 5, by the way,) is inherently inferior. Not impossible. And there are no rules in drama that can't be profitably broken by someone sufficiently creative enough.
But returning to the question of what is a good story and character, it may be that social decay is leaving people disengaged from the world. They have less and less power over their fates and at some level they must realize that the future is not theirs, nor their posterity's, but that of their masters. It is natural for the weak to take refuge in fantasy, particularly personal fantasy. The open-ended serial very much tends to indulge in the central characters' personal stories, even to the point that there isn't really much else in the fictional universe besides a few talking props. The much vaunted character arcs substitute fantasies of personal reinvention leading to success, love, fame, power, while the social vacuum allows such daydreams undiminished by the harsh light of reality.
These kinds of dramas are inherently limited to personal tastes and there's nothing to say about them, for there's nothing really there. Nothing, that is, save frustrations at not having the proper day dream material suitable to one's personal idiosyncrasies.