The government intervention in the markets for agricultural products is because farmers are often an important political base, not to keep prices low for consumers. Without the intervention, prices would fall and supply would have to fall too, which would be good for consumers and bad for producers.
I'd argue that government intervenes in agriculture for supply-chain safety first and foremost.
Governments are concerned with this because no meat (or rice) on supermarket shelves during a supply-shock of any kind leads to rapid unplanned regimechange very consistently.
So basically every western government throws a few billions a year at local farmers so they stay (and this is not a US phenomenon, EU does the exact same thing). This is also less necessary for countries where labor is cheap.
This is arguably good for most consumers because essential calories being more affordable "on average" is not good enough, you'd typically rather pay (partially indirectly) a higher average to guarantee availability and avoid starving.
