Honestly the gasbag looks nothing like a water bear. Explain why it has a beak not a circular mouth, it has antennas which water bears don’t have and it has six legs while water bears have eight. So I think it should be reclassified because of those reasons that I talked about. I think the should be like some sort of species of turtle. I know it sounds crazy but hear me out. First they have traits of a turtle such as a retractable neck and a beak. Plus most turtles especially sea turtles have a wide shell or body and large lungs. A great foundation for a large bulky body. And because the gasbags are living in an extinction event, over the many years they could have adapted to the wasteland over time. And turtles have been known to survive mass extinctions such as the one that wiped out the dinosaurs. So I think gasbags evolved from turtles. Of course there are some holes in this theory like why do gasbags have hair, antennae and six legs. But remember evolution can work in strange ways.