[lordnacho]

Just watched this, thanks. My summary:

1) Staff turnover roughly around season 8 caused the writing to change. Jokes got simpler, not as much about the characters' invariants (for lack of a better term).

2) The show was originally successful because it parodied the sitcom era of the mid 1980s. That changed so the context disappeared.

[saganus]

I think your summary is correct, although I would add to point 2 (or a third point) about the complex nature of the jokes.

They weren't just one liners but instead would build up gradually.

That's what I like about this analysis, it got me to understand something that I somehow felt but had no idea that it was actually happening.