Then why isn't Wally West the Flash, or John Stewart the main Green Lantern?
Because that's not what Geoff Johns grew up with.
The moves to bring back Hal Jordan, Barry Allen, and the pre-Crisis
Legion of Super-Heroes make perfect sense when you think about what DC was publishing when Geoff Johns was a little kid buying comics at the 7-11. Today's DCU is based on Johns' memories of the Bronze Age.