I'm pretty sure all this has been said before, but I'd still like to bring up the topic again.
Many individuals would say something like, "Oh my gosh! How did they not know it's them?" Or something of the sort when discussing the topic of superheroes and their modern day form.
One to name in particular is Miraculous Ladybug. Many people always say something along the lines of, "How do they not know that Marinette and Adrien are Ladybug and Chat Noir (respectively)?"
Naturally, that's simply how we - as an audience - see them. When I say this, I'm talking about this for every superhero comic or show and for anything 'Magical Girl' type anime or whatever.
The audience knows the identity of the heroes, but not the actual people within the show/comic.
Now, let's pretend that we were one of those people living inside that very comic/show. We wouldn't know the identity of them, or perhaps even place two and two together. Of course, we have the mental capacity to be like, "Oh! [Superhero] is here, but [Modern Person] isn't!" with the realization that it happens often, and place that all together.
However, maybe there is something that goes along with the powers.
Like in Miraculous Ladybug, maybe the Miraculous given to Ladybug and Chat Noir influence each other and the Parisians that they are other people. Perhaps that can't recognize the identities due to some sort of magic that toys in there mind.
To be frank, I don't know exactly what it is really. What do you believe?