I stand corrected, but I will say that a lot (all?) of Hammond's appearances were as recurring real-life characters (Trump, Schwarzenegger) who were in the public eye for various reasons. Unfortunately, David Dinkins hasn't done anything newsworthy lately. So they had an excuse to bring Hammond back in those cases,…

I was all set to say "Coneheads" didn't do too badly, then I check Wikipedia and this little nugget comes up:

I'm pretty sure Gary Kroeger, Tim Kazurinsky, Tony Rosato, and Brad Hall have been erased from history in general, not just from the show.

Yeah, but Darrell Hammond was on for longer than Meadows and you don't see anyone clamoring for his return either (mostly because it was revealed that he's completely bugfuck nuts, but still).

Wasn't Alec Baldwin in a couple of those Brasky sketches? Did they ask him to take part? If not, I'd expect Lorne's got a pretty salty voicemail waiting for him when he comes into the office next time.