>>364079Streaming killed it. Dumping episodes online for people to watch it at anytime made it non-uniform for people to get into the series at the same time and have discussions over it. People may talk a bit about some big new tv shows but since they saw the whole thing all at once, after a few weeks (at most) social discourse is done.
Though the closest series somewhat comparable to the old days like GOT might be The Boys. Mainly because Amazon Prime releases the episodes weekly instead of all at once, and I've seen people discuss it online episodically. Though there's only 8 episodes per season and seasons don't come out annually, so far The Boys managed to keep itself relevant among the masses through memes, plus Homelander becoming an iconic villain.