This question can be answered by just a bit of research using your friend Google. I like sum-it-up by saying that it's all about making your editor work for you as opposed to simply being a blank slate on which you can type.
Simply thinking that the hotkeys are esoteric is missing the entire point of the command structure which is effectively a language for text manipulation. Google for "vim nouns verbs" for some great descriptions.
"work for you" might not be the right message, as that is what IDEs are known for.
I'd say that vim makes you faster. It's like talking with your close friend vs talking with a stranger. You understand each other better and can speak very quickly. High bandwidth communication maybe?
I agree; it's tough to write out the semantic difference between an IDE "doing work for you" and Vim "working for you," where the former is tools doing tasks you don't want to do and the latter is the editor providing a language for you to give it instructions in far more evolved way than the primitive text-editing concepts of many other editors.
Simply thinking that the hotkeys are esoteric is missing the entire point of the command structure which is effectively a language for text manipulation. Google for "vim nouns verbs" for some great descriptions.