I agree that erosity does not tell the whole story, but MD is one of the most gerrymandered states. It's just not the most gerrymandered for purely partisan reasons. It's an incumbent gerrymander, which is still a gerrymander.
The DK 8D plan also fails neutral principles. It relies solely on compactness, but minimizing chops of political subdivisions is as important as keeping a low erosity. Together they give a better picture of whether there are gerrymandering goals. It also looks like the DK map ignores the VRA, fracturing black areas to get better partisan results, so I'm not sure it's constitutional.
nb. Erosity comes from erose meaning irregularly toothed, notched, or indented. It's usually used in botany to describe leaves, but some of us like to use it for districts, too.