I don't really see a mismatch. He's naturally timid, jumpy, nervous and prone to overthinking. He would be a wimp - if he let that stop him. But he doesn't - by overthinking and relating everything to the shounen hero stories he loves, he is eventually able to overcome and face his fears. That puts him head and shoulders above like 90% of male MCs in romcoms.
I used to be terrified of dogs. That was my natural inclination. Eventually I decided I was too old to still be afraid of dogs anymore, stopped avoiding them wherever I could, and now I'm at a level where I'm only afraid of dogs that are actually dangerous - huge ones that snarl and bark. I had to think my way through my fear. It's the victory of the super-ego over the id, so to speak.