Why would a guy ask you if you would date him?

I think it means he was asking you on a date in such a way that if you said no he wouldn’t be overly embarrassed.

He wanted to know if you would (hypothetically, should the stars align, only if you really want to, but don’t feel any pressure because I could easily be joking, or not, ‘cuz you’re so cute) be inclined to date him.

To which, you said, “I don’t know.”

Seems to me, you need to think about it and give the guy a more definitive answer.