Yes, I was being sarcastic. Sorry about that.
I guess you could close down the park, but places like Yosemite and Death Valley have State highways going through them. You cannot shut those down, These places are not fenced in, so its tough to keep people out.
There are a lot of people who just think the world will clean itself up.
If this stuff is happening now...wait a few weeks. This could get a lot worse.
Restrooms and Trash Removal
National Park Service-provided services are limited. Restrooms at or near concession facilities remain open. Facilities not located near concession facilities are closed due to reductions in staffing. Dispose of trash in a dumpster or trash can that is not full in order to protect wildlife and avoid a citation/fine. Do not leave trash on top of or next to a dumpster or trash can, or stuff trash into a full one. Carry your trash to a dumpster or trash can at a hotel or store that is open and has a dumpster or trash can that is not full.