Maybe it's an explanation for laowai of how to use the shower at the gym.

I think the explanation is........ "Crickets Need a Break Too!" Notice how the crickets are enjoying massages, dips in the pool, and hair cuts. The life of the cricket can be a stressful one, so these smart crickets are taking time to unwind and pamper themselves.........etc.

Was this a museum of things prisoners make out of matchsticks in
their spare time?

I now have a new found respect for crickets. Obviously they can be so much more than I thought they would ever be.

We decided that it was either a very old cricket beauty shop, which included resting and getting your hair done. Or it was a foster home for orphan crickets and the foster mother was washing one of the children's hair. One of the others was drying her hair and the third was toweling herself off and ready to take her nap on her bed. These are obviously female crickets, which would be discarded in China, so they have to make the best that they can.

We could carry this further and say they are prostitute crickets getting ready for their evening's activities, but I didn't see any salacious clothing or pictures or equipment. So, I don't think that's the case.

Could this be a typical dorm room in a cricket university on a weekend?

I think that it is a depiction of life under the wrath of communism...it can't get any better than that of a cricket (except people don't get eaten) cause everyone is so equal.