It could add a much needed impetus for the semiconductor industry to consider security perspectives in a much wider sense.

Today we can't know or analyse the security properties of the silicon that essentially runs the entire world. We simply have to trust the producers, and they have been proven to be unreliable at best. They compete on performance and features, and the result is not that different from when there were no safety regulations (and testing) for cars, except that so far bad processor security haven't killed as many people as far as we know.

Open IP is one way to help making sure the above stays true. There are certainly other avenues, but for security it seems to be the case that it's best handled in the open.