I think a lot of people are going to be too far upside down to sell theirs. There won't be a big influx of used ones for many years.
I'm a proponent of buying an RV when you're ready, not waiting around for the right deal to come along. If you want to get out there and travel you need to do it while you can. Life happens, and illness, injury, personal obligations and other factors are always out there to get in the way of your future plans. We have two relatives who have had to drop and/or substantially modify their plans to travel, recently. One passed after a brief fight with cancer, and the other had a stroke that will change their life forever. It might be getting slightly off-topic, but I think the idea of waiting for the right deal is waiting too long. We sold our house and went fulltime in our 30s, because who knows if we'll be able to enjoy it or even be around come retirement age.