If you were in charge of controlling the political party's and politicians for the cabal and it took you millions of dollars, years of hard work. Would you want to have to handle more than 2 parties? The more parties, the harder your will have to work.
After years and years of placing your politicians, infiltration and getting control of the 2 party system would you want your politicians having term limits?
Imagine all the work having to get a new corrupt controllable candidate every 4 years.
2 parties, no term limits is by design.