Stopped reading right there.

You don't need to provide a wall of text why I'm not the right candidate. I don't intend to read your summary of my resume. There's really no point. I'm already in a mad/frustrated/disappointed/etc. state and giving me a great wall of text is adding insult to injury.

Engineering candidates are really looking for feedback on how the interview/technical component went. The "cultural fit" answer is a blackbox and stating it doesn't really answer what you're looking for.

You're better off just telling me I'm not the right fit and for legal reasons, you can't go into details. That's really it. Don't tell me about what you think of my previous experience. Don't tell me about the other candidates (frankly, I don't care unless they become my co-workers).