Her losing the belt was bad for WMMA.. it needs people like her and Cyborg (and even Ronda before she got mega-exposed) to look unbeatable so it seems like there's actually a skill gap. It's a bad look when someone can come in and smash the champion like that especially when that person has losses to people who couldn't beat the champ.
I'm a fan of Joanna but I think you're talking out of your ass if you think there was such a big skill gap between her and Rose.
Rose sharpened her skills over time and it was destiny for the two of them to meet as long as Joanna stayed on top.
Like Rose said, she studied her opponent and cracked the code.
There's no saying that method will work again. You can be sure Joanna's working hard not to lose again, but Rose has a deep tool box.
On a sidenote, I will agree that some of the people Joanna faced during her run weren't exactly of the same caliber.
Even if the powers to be want to pick and choose who fights who possibly favoring one fighter over another, but this isn't scripted. As the saying goes, "anything can happen in a fight".
Maybe it's a bit early, but I feel like UFC are gunning for Joanna to win again judging by the amount of promo of her they're pumping out. Meanwhile, Rose is busy at the gym.