The point of the story is that
1) Mobile homes are horrible investments. They go rapidly down in value. “cars go down in value. Mobile homes go down in value. It’s a car you sleep in.”
2) Private equity groups such as the Carlyle Group, TPG and Blackstone now own large tracts of mobile home park and collect big fees.
3) Loans for the houses have large interest rates. They have to be. If you sell a product and give a loan that goes down in value very fast, only way to do that is to charge big interest because the risks are also big. Poor people don't have other collateral.
This kind of rent seeking form land and loans where poor people pay and pay means that people stay poor. This would be a job for government. Provide cheap rented land and basic infrastructure and cheap mobile housing.