Absolutely yes. Dehumidification typically involves a full refrigeration cycle. It's like leaving a refrigerator running with the doors wide open, the only purpose being to drain out the few drops of water that drip off the condenser coil every minute. Not a very productive process.

And any process which provides energy-free dehumification would also have the secondary (or primary) benefit of providing energy-free freshwater.

I'd imagine they've thought of both the above applications, and their protein nanowires aren't suitable.