It might work at distances longer than 300m, but "they ran out of space on the dock." That seems like such a silly limitation to bring up twice in the writeup.
I agree about academic press releases generally, but it seems to work as described? If their model is right and they build a larger prototype, which is normal scaleup from academia, a kilometer scale underwater RFID tagged sensor buoys responding to a transmitter seems like a reasonable if optimistic claim. They can't build that before modeling, and they can't model without a small scale system to cross-calibrate with.
This press release actually seems better than most to be honest...
This isn't a product that's already on the market, so what matters is how far it can get if actually commercialized - which is pretty impressive at such low power.
If it’s “long distance” put the unwieldy piece where you have reserved space and move the less complex piece to borrowed space. Like another jetty, or a beach, or here’s a crazy idea: on a seaworthy vessel. You know, to test your marine communications device on a marine vehicle?
..., but not a single trail on a rowing boat to see how far away they can go until the signal breaks down.