As someone else in academia who gets his share of crackpot emails, no response can also mean "oh god, I don't have time to think about this when I have 1000 oth

As someone else in academia who gets his share of crackpot emails, no response can also mean "oh god, I don't have time to think about this when I have 1000 other emails from my students and colleagues". (I'm particularly horrid at email.). So I wouldn't take it personally.