What he wrote was extremely arrogant. Unless he tried to be funny. I am tired of people who tell you that you are doing it all wrong after a quick look.

I work on a pretty complex system myself and every few months somebody comes in,takes a quick look and tells us we just need to use framework X and all will be easy. Guess what, we are not totally stupid and have looked at it already. And it wouldn't solve the actual problem which is that it's just a very complex thing we are doing.

First understand what people are doing before telling them they are wrong.