Twilight didn't invent the usage of vampires in fiction; but Twilight's popularity spawned the idea that vampires in fiction is very trendy. Which is now true. True Blood and Vampire Diaries probably never would have launched without the popularity of the Twilight saga. And because those three were all released so close together, people who weren't "trendy in love" with vampires got sick of them really quickly. The market got flooded with vampire material. And by most people's standard it wasn't even good vampire material. If someone can create good vampire fiction that doesn't break the boundaries of the mythos and doesn't look like it was done just because "vampires are cool" then I doubt there will be many people crying foul. But then there will always be the "YouTube commenter" type of people who get stuck on their own trends of criticizing everything they possibly can just to look smug, cool, or to troll. But those people don't matter anyway