X-people (come on let's introduce PCness into this) could have been operating like witches and wizards in the Harry Poter universe. Totally underground until the opening X-men movie under the MCU, which is when they become a more widely known sub-species of humanity. Piece of piss really.
Spiderman will have no origin movie, so the MCU simply does not address when Spidey got is powers. COuld have been before or after the first Avengers movie. Doesn't really matter. He's been operating off the radar, but he comes to the attention of the Avengers during Civil War.
“The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt.” - Bertrand Russell
"When the power of love overcomes the love of power, the world will know peace."
Jimi Hendrix
