It\u2019s weird that for so long the prestige, \u201cprime time\u201d model of TV was basically character types in disconnected but formulaic vignette plots and \u201cmulti-episode plot arcs driven by changing character dynamics as plotted by a coherent creative team\u201d was the degraded, low-status daytime \u201csoap\u201d form
People date the \u201cGolden Age of TV\u201d to The Sopranos but I think the key was reversing this and that started in the decade prior. By the time it debuted in 1999, Buffy the Vampire Slayer and Xena: Warrior Princess already had a real reputation for that (and for playful writing with self- and genre-awareness, which was impressive when you consider they were both based around fight scenes); the X-Files was famous for balancing monster-of-the-week and broader series mythology.
You can see the progression in the Star Trek serieses - TOS was barely consistent from episode to episode; TNG had the Borg arc and recurring Q episodes but also the entirely abandoned Season 1 arc about corruption and betrayal in Starfleet; by DS9 they kicked off the series by plopping the station next to a blob of long-term plot and introducing elements \u2013 Sisko as Emissary of the Prophets \u2013 that didn\u2019t resolve for seasons.
Maybe further back to the 80s, when this even became possible as shows staffed up their writers\u2019 rooms enough to produce consistent work in-house rather than just taking freelance pitches and polishing them. Miami Vice was a breakthrough not just for the cinematic style and contemporary pop score but that it had elements of overarching plot \u2013 the hunt for Calderone, Sonny\u2019s amnesia (how soapy!) \u2013 at all
"}