They were all from Oxbridge and the weirdness specifically satirized British culture of the 60s and 70s. It just so happened to be universal enough for an American audience to appreciate “a bunch of dudes in dresses being weird for weird’s sake”

Compare to something like SNL which would be unfunny to a Brit unless they had some specific interest in American culture.

I'm not saying Python was rocket science, but while it had a lot of broad humor (Ministry of Silly Walks, etc) there were also a lot of subtler jokes.

    I thought it was just a bunch of dudes in dresses 
    being weird for weird's sake

A lot of the jokes might have been misfires for you because of subtlety, cultural differences, references that are completely obscured by time 50 years later, etc.

Or maybe just not your brand of humor! Certainly lots of people think much of Python was funny.

The Philosopher's World Cup is a pretty good example.