If the cruise ship terminal is modelled after the one in Majahual, Quintana Roo, it may not have as much impact on the locals as you might expect. At the Majahual one, there is a 12-15 foot high block wall all the way around the pier area with guards at the gate. Inside the wall are shops and cafe's that are leased and operated by non-local companies. Locals are not allowed through the gate unless they have a work ID; Not even cab drivers. This also applies to non-cruise tourists, like RV'ers. I have no idea why.
However, cruise ship passengers are allowed out of the gate where they can rent bicycles or scooters and even can catch a shuttle over to the malacon, about a mile away. So the locals do profit from that. But most board busses that takes them to the Mayan Ruins about 80 miles away. During the season there are 2 to 3 cruise ships tied up every Monday, Wednesday, and Friday for about 8 - 10 hours, so we had the place to ourselves 4 days a week.
By the way, the Mexican Government didn't build or pay for this cruise terminal, the cruise ship companies built it, Twice! The first one was destroyed by hurricane Dean in 2005. So I'm not sure why the government is getting involved this time. I just hope they have actually talked to the cruise ship companies about their plans.
At Majahual, the government did build the mile long malacon and part of the little town outside of the gate. There are blocks and blocks of building lots with paved streets and all the utilities already installed, just waiting for someone to buy and build on them. But they have been there, empty, for about 5 years. The locals rebuilt the fishing village themselves.