This is a major claim.  Read here to decide for yourself.

“President Roosevelt believed that excessive competition was responsible for the Depression by reducing prices and wages, and by extension reducing employment and demand for goods and services,” said Cole, also a UCLA professor of economics. “So he came up with a recovery package that would be unimaginable today, allowing businesses in every industry to collude without the threat of antitrust prosecution and workers to demand salaries about 25 percent above where they ought to have been, given market forces. The economy was poised for a beautiful recovery, but that recovery was stalled by these misguided policies.”