Obviously I can't say for sure, but to me "you're a pretty cool guy, but I don't have time/space in my life for new people" sounds much more like a polite excuse to avoid saying "you're not somebody I want to be friends with" than an accurate statement about the reason they can't be friends with you despite honestly feeling you and they are compatible friends.

edit: But maybe that's my British instincts wrongly diagnosing a statement that I have no real context to judge better.