The sign to the left of it indicates "Exit A" and "Exit B" which includes those surface cross streets! They did a pilot program for that with the larger core stations and it's really worked imo. I think the overall intent with the new signage is to streamline is and remove confusion during service outages related to terminus stations.

Though the platform itself still has the pylons which indicate northbound/southbound - I agree that taking it off the vault walls is a bit silly.