New Brevoort Formspring

Hi Tom , had a great discussion at my regular nerd waterhole and Marvel X-men was the topic and got a question for you sir. We were talking about the 90's when Bishop came from the future he had grown up with the history of someone betraying the X-men who he thought was Gambit. but after AOA we the fans and Bishop himself found out who the true culprit was. My question is why hasn't Marvel done this more? Why are now all Future timelines just an alternate why can't story come full circle?