Except for Spider-Man: Homecoming, Marvel movies have almost entirely done away with the concept of secret identities, and Black Panther fits nicely into that mentality.
His fear factor does not stem from a mysterious origin or a sense of confusion around his mythology; it all stems back to the fact that the arrival of the white skull (just like Black Panther’s mask) carries a scary connotation.
For example, on the streets of New York City, most criminals know that The Punisher’s real name is Frank Castle.
This idea presented by Chadwick Boseman during his appearance on Jimmy Kimmel Live! has become a fairly common concept in the world of Marvel over the years — the comics, as well as the Marvel Cinematic Universe.