Are there even any more shared cultural moments/experiences like that anymore? The closest thing I can think of is maybe large sporting events, but even then, they seem much less impactful than before.
There are still streaming shows that drip feed new episodes (S2E3 of Severance releases tomorrow for example) but it’s still somewhat diluted because there is so much content, it’s likely you don’t run into too many people who watch the same stuff as you. I can’t imagine a single show whose finale would have Times Square staring up at the screen like Seinfeld did.