It does make sense that less populated areas tend to be naturally less statist (Thomas Jefferson had this one figured out long before population pressure was a big issue).
Neighbors too close are often a nuisance. Nuisances are breeding ground for government interference.
A hundred yards between houses makes neighbors more appreciative of each other. Instead of being a nuisance, they are valued and needed neighbors.
Infectious statism breeds and multiplies where are more than a hundred people per square mile.