I can't say about the original watching (Thursday night line-up?) but I agree that Frazier holds up. We just completed an all-seasons rewatch, and they still really made me laugh.
One thing I noticed having rewatched again. My only minor complaint
Too many episodes rely on the joke structure of someone coming into the room just as some leaves for like 5 different people causing the misunderstanding
I think that was done at least once a season, with the cabin episode being the one that pops into my head