It's especially hilarious because he is comparing projects done by bootcamp graduates to projects done by highly trained PhDs. Some people just don't have a clue about the massive difference involved in webdev type projects and complex engineering projects.
That is just the mathematical description of gravity according to general relativity. We don't have a theory for how the uneven curvature of space happens and we don't have a quantum mechanical theory for gravity either (gravitons are hypothetical, not proven).