I think (and I don't believe its a new hot take or anything) that honestly the most terrifying thing about Batman beyond the insane detective intelligence and the crazy fighting skills and the gadgets... It's his ability to emulate the "scary creature" vibes perfectly.
Yes, Bruce is a bit of a weird fucker, being a grown ass dude running around in a bat-themed costume and obsessed with justice, BUT THERE'S A SERIOUS PSYCHOLOGICAL WARFARE COMPONENT TO IT ALL. Certain visuals freak people out because it doesn't line up with our preconceptions of what animals/people look like.
The batsuit generally (and boy has the batsuit been through far too many iterations) has key components that lend to the scare factor. No visible human ears, the "bat points" being slightly pointed and almost devil-like. Already a red flag on a visual level if you see that kind of thing on a humanoid figure. Add in the white-out lenses that glow in the dark and the huge cape. Yeah, dramatic as hell. But wouldn't you be super terrified of seeing a silhouette like that? White eyes staring right at you?
My own personal comparison: one time I was bopping along a very very craggy shore far up in northern California. There were cliffs and caves, barely any actual sandy beach to explore. I was dumb enough to go out beach-combing with my super old dad (75? 75 old ass man on the rocks? What were we thinking?) close to dusk. There's barely any sunset left to make it easy to see. Dad is determined to go check out a cave. We get close to the cave.
A pair of glowing eyes and very pointy ears stare right at us.
Immediate fear response. Because creatures like that? BOBCATS. We backed away and scrambled back to the motel SO FAST.
Bruce designed the suit to invoke panic via the good ol' fashioned lizard brain panic. Mix in the fact he's humanoid-shaped and the DCverse is full of aliens, werewolves, metahumans, and all sorts of crazy characters in-between, it's the perfect kind of fear-invoking psychological warfare.
