One show is produced with edits and retakes if someone flubs a line or breaks, the other is live. Also consider, SNL puts out more content in a single season with 22 episodes at 90 minutes, then all of Monty Python's full run of 45 episodes at 30 minutes. You're comparing apples to oranges.
Sometimes you look at an orange, and think how convenient it'd be if you could bite it like an apple. Okay, many don't, but few who do came up with all the modern fruits :)
You would think that 20 episodes a season over 50 years, then on just pure statistical probability they would have had a funny skit. An infinite number of monkeys on an infinite number of type writers will eventually write a funny joke. But somehow, against all odds, despite hiring comedians, comedic actors, improvers, and writers. They have never, once, gotten a funny skit. It defies belief actually.