9. Peter Parker Would Have To Be Dead
How else could you explain Peter Parker's absence? Short of wiping him from existence and having Miles be the first person to become Spider-Man, why Peter isn't in the next set of movies would need to be addressed in some fashion to fully satisfy fans. Who knows, perhaps The Rhino just killed him when the screen faded to black at the end of The Amazing Spider-Man 2? What a kick in the teeth that would be for Andrew Garfield. It's already going to be awkward enough for Marvel to insert Spider-Man into their Cinematic Universe without getting into any overcomplicated explanations about the first Spider-Man having been killed, so just bringing Miles to the big screen without any confusing backstory is obviously the simpler option. Not even acknowledging Peter Parker runs the risk of alienating fanboys though, but there's an obvious solution to that issue. Just introduce Miles a few years from now after this new Peter Parker has been established, if you really have to.