The people likely to benefit most, with the Expert Market as with the unsolicited quotations, are toxic funders. Not the companies themselves, because many of them no longer exist.
So the MMs will get a little more traffic, but not a ton, so I doubt they really care. Sure, now executing trades in these stocks is easier for them, because they don't have to call around. But they aren't required to execute trades for Greys, so if they don't want the trouble, they don't need to bother.
So I really don't know what OTCM has in mind. I do know Coulson is a big supporter of pretty much laissez-faire markets. He supports the idea that anyone should be able to trade anything at all, it seems to me.