If it's shocking for Naomi to not be in Senbatsu, then it must more shocking for Sinka not ranking in Senbatsu. I feel like Sinka was given a lot of opportunities from 2016-2017. Fans voted for her to UG center perhaps because they felt Sinka was underrated. Now that Sinka is given more and more opportunities, they slack off or not powervoting her anymore feeling that she has gain enough fans. Could be an old-KIII-hakooshi thing too, but idk. The thing with Sinka could be that despite given many opportunities, she didn't successfully attract new fans. Love Trip for me was boring. You could blame this on JOT's lacking marketing power, too, methink.