Comments in this thread are all discussing the wrong topic. It wouldn't matter if 100% of corporate board members were women and minorities due to how boards are constructed over time through shareholder "elections".

Corporate boards are not a free market of ideas, they do not support or represent shareholders, society, or employees, they are monopolized self-serving power structures representing an extension of incumbent management.

Introducing diversity into a situation with already-disfunctional power dynamics (which drastically favor incumbent management because all votes not cast are cast in favor of incumbents) obviously have no impact. Corporate governance laws and proxy voting processes changing is a prerequisite for marginal board members to ever have any real power.