Nobody is a genius all the time.
Isaac Newton nearly blinded himself by probing his eyeball with a needle. Albert Einstein often got lost on his way back home. Elon Musk’s twitter handle showcases his several moments of weakness.
Everybody is a genius sometimes.
Genius is the worker on the assembly line who tweaked the process to save millions of dollars. In a burst of genius, your friend might have mentioned something in passing that forever changed the way you looked at the world. You have been a genius in the moments when you have have brought a unique perspective to a problem and made a contribution that nobody else could have.
If you followed around a person you consider to be a genius for an entire day, you can see how anybody can do 90% of what they do. For a large part of his day, Elon Musk drives around LA, writes emails, attends meetings and spends time tweeting. Yet, for a few moments each day, Musk sees the world in a way that only he can. Those few minutes where he channels his genius is what sets him apart.
Nobody is a genius all the time. Everybody is a genius sometimes. It is merely a question of who is channeling what.