This isn’t really true. The massive corn subsidies result in much lower feed prices than you’d see in a non-distorted market. It’s not a direct subsidy, but it does have a pretty direct impact on a feedlot’s bottom line.
I’ll grant that point. Livestock producers benefit from cheap feed. But other governments support their meat industries in various ways (direct and indirect supports, restrictive trade policies, etc.) and if you adjust the cost of the final product for the cost of feed, the U.S. is still very competitive/