I tried watching it because it's a classic that everyone talks about. Couldn't get past the first 20 mins. It just wasn't for me.
The whole thing of Monty Python is they are so stupid, you have to laugh.
I think if you were born after 1970, the British humor of TV and movies featuring comedy of Monty Python and others just won't strike your funny bone.
There's been a running joke forever that the British don't "get" American humor, and vice versa.
The stupid graphics is a good example. They spend a lot of time on the drawing with elaborate and ornate backgrounds and detail (almost looks like Michelangelo level artistry) and then they animate it by just moving the mouth and eyes! It's like a kid with a new camera is playing with stop action photography!
The Holy Hand Grenade, a cow in a catapult, a knight with no horse being followed by his squire clapping 2 coconut halves together making a galloping sound effect. Or the scene where they try to logically determine if a woman was a witch.
It's supposed to be stupid. Whether you find it funny or not is a different matter. Sometimes it does take several times watching with people who appreciated it before you see the humor in it.