The only really new thing in there is the genetic diversity. Some of that paper is a straight up thought experiment meant to persuade, not report findings. For example, the bit about flowering bamboo and how they must have endured thousands of such events in 8 million years. In rebuttal I would ask how do the authors of that paper know that the population hasn’t been getting whittled down by such events, bit by bit. They make suppositions about ranging farther for food, but again provide no findings. There are multiple other problems with the paper, including mischaracterizing their own tables but I’ll leave it there.

I will say that paper does a good job summarizing the position of people saying they will go extinct. By the way the full paper is freely available at Molecular Biology and Evolution. I would love to be wrong, they are very fun to watch. And if they can thrive with their habitats reconnected and protected then that’s great. But I’m also not going to be surprised to find out it’s just not in the cards.