I don't disagree. I'd like to see Whittaker vs Strickland. However, Strickland IS NEXT. If you can't see that, then you must be a blind hater that just doesn't like Strickland. If Izzy loses, he's not getting a rematch. If Izzy wins, DDP isn't getting an instant rematch and the Izzy/Strickland rematch becomes the most logical next title fight.
There are scenarios where Strickland sitting out works against him, but they are not likely. Khamzat could beat Whittaker and make it look easy, allowing the UFC to push him ahead of Strickland. Not looking likely right now, and without beating Whittaker, Khamzat can't earn a title shot with a single win at middleweight. Another scenario is the DDP/Izzy winner is injured and can't fight for close to a year, and the division keeps moving during that time leaving Strickland behind. Whittaker with another 2 wins would put himself ahead of a Sean Strickland that's been inactive for 12 months. The last scenario is that Strickland himself gets injured when the DDP/Izzy winner schedules a title defense, and the UFC subs in whoever is next in line, and again Strickland ends up going 12+ months without a fight, and is no longer the obvious #1 contender.
But assuming everyone stays healthy and the DDP/Izzy winner fights 6-8 months after the upcoming fight, then Strickland is the #1 contender and not much can change that.