It’s not just WA. It’s everywhere. New campgrounds are popping up fast and people are becoming disenchanted with the failure-prone covid wagons, so I don’t think it’ll be this way for long.
I imagine it'll die off because as you point out, folks will find out that RVs always need something, and in a lot of ways are kind of a pain-in-the-ass. But, man, thought it would have happened by now.