I can agree with that. I hate that so much comedy today relies on vulgarity or gross-out humor.
1. Well it was definitely the golden age of physical comedy, I can agree with that. 2. I think it evolved. The physical gags weren't used as much in the sound era, but they didn't completely disappear. 3. I know personally, I am hugely influenced by documentaries. They give me fresh views of things I already knew about or introduce me to things I never knew about.