The “/s” is Internet forum code for “sarcasm” which is a type of humour. This indicates the author knows it’s not true, but perhaps thinks it’s it would be funny if it was true.

Many (most?) bills that have contributed to skyrocketing prison populations have actually been straight up directly written by private prison industry lobbyists. In one case a senator even accidentally left the logo of the lobbying group on the proposed bill

Because US has the best government that money can buy.

Jokes aside, the government and the largest market players are extremely intertwined.

In the US, politicians are bought and sold. That’s the Free Market.