Is the work of Monty Python, as a rule, on topic here? The world, as depicted in Monty Python's Flying Circus is different from the real world in many ways. One can suffer a dangerous fall while climbing the North Face of the Uxbridge Road. The British Dental Association is one of the world's premier spy agencies. And Mister Neutron is so powerful, he could destroy the whole world.
Of course, the show has no continuity, but clearly anthology shows like The Twilight Zone are on topic. The one episode of the Circus that has a single running plot is the Mister Neutron episode, which is certainly SF (as well as possibly the worst episode in the show's whole run). There are also other sketches with clear fantasy or SF character.
Personally, I would be inclined to think that only stories/sketches with meaningful fantasy or SF content really should be on topic. That means the entirety of Monty Python and the Holy Grail, probably The Bishop sketch, but not the Cheese Shop Sketch. But what do other people think?