Wasn't Mike Davis talking about different ball specs for different courses, rather than different ball specs for the pros vs amateurs?
I don't see the Tour ever rolling back to a shorter ball. As others point out, I don't want to go watch pros hit the ball as short as I hit it. But I wouldn't mind seeing the next US Open at Merion played with a shorter ball, while Opens at Erin Hills continue to be played with a ProV1-type. And having different ball ratings for different courses seems like it would help the equipment companies sell even more balls, and seems like it would help the USGA make the game even more expensive for players who would have to stock up on more equipment and keep track of yet another tedious rule on top of the original rule of "Hit ball, find ball, hit ball. Continue until in the hole."
In other words, it seems like exactly the kind of thing the USGA would do.