High quality TV is downstream of On-Demand viewing.

Before DVRs or On-Demand, people could only watch an episode of a show if they were tuned in at precisely the right time.

Some shows were so culturally relevant that people would reorganize their lives to be able to watch it.

But the vast majority of shows didn't rise to that level, so they had to assume that most viewers had missed at least a handful of episodes.

That meant that multi-episode arcs were less likely to work for viewers.

Arcs had to fit within an episode, and then reset back to basically-the-same status quo.

If characters can't change over time, then you lose a ton of potential nuance.