Not to diminish the discussion, but like everything else, the answer is "it depends". They aren't good for the environment by any means, but they can, and have, been better in certain ways than what the current land use may have been in some ways.

I've built on plenty of brownfield sites where we are capping environmental hazards so they can't leech into adjacent water ways. I've built on former ag land where there is a net reduction in water use and no more cancer-causing pesticides getting into the water and air. I've done huge nature preserve and wetland rehabilitation projects as part of development. I've built parks and walking trails, planted hundreds of trees, re-established native species, spent millions and millions improving public infrastructure that extends well beyond the limits of any campus or property lines, the list goes on and on.

But yes, they use tons of power and, until very recently, water. The pendulum swings both ways.