>Talks about cargo capacity in terms of TEUs (shipping containers, I guess) rather than gross tonnage, which is the way we've always talked about ships forever.

Gross tonnage has little to do with cargo capacity, as it covers weight of hull, machinery, fuel etc. Net tonnage is more relevant, but it is not a good basis for comparing the capacity of different types of cargo ships. TEUs are a good way to compare container ships to each other, so at least in that respect the article is fine.