Chris Farley died, Tim Meadows actually retired after 20,000+ years, Dennis Miller is doing his own thing, a bunch moved on to movie careers (David Spade, Adam Sandler, Will Ferrell, and many others). The rest of the greats have moved on.
Basically the new cast sucks bellybutton and has sucked bellybutton for quite a few years now. Horatio Sans is ass, and Jimmy Fallon, how the shreck did they find him anyway? Sandler clone - and a horrible one at that.