Doubt there is one size fits all answer. Some will continue to slowly spiral down, eventually becoming essentially low income, trashy, trailer parks. Some parks will become pro-active about appearances and enforce rules to force the owners to either update and upgrade their units or move them out. Others will reinvent themselves into something else.
Someone mentioned experiences vs activities. Those parks reinventing themselves might do something along those lines. Sell themselves as base camps for a host of activities, both organized by the park as well as taking advantage of their location. Basically dropping pot luck bingo and replacing it with an organized group trip to the theater etc.
A marketing campaign focusing on the fact the surrounding area has 200+ different restaurants, miles of hiking and biking trails, 1000s of acres of public lands, and every other potential activity will draw new blood even if they never patronize any of it. Shuffleboard, bingo and a model train club will probably not create waiting lists to buy park models in the future. Kind of like how all the home selling shows have the buyers focusing on how great the spaces are for entertaining, even though they probably entertain 5 days a year and use that space for living the other 360. It's the vision of great parties, not the fact they have to clean that additional square footage that people focus on. Selling the sizzle, not the steak, will become very important to the survival of those communities.
