in many places the population distribution is such that if a party has that sort of advantage then its perfectly fair for them to retain it; since that's one of the inherent things that First Past the Post does and if you are breaking up communities and intentionally drawing seats on a partisan basis then, well, that's gerrymandering by itself. I don't know anything about the political geography of Maryland but if its a state which is politically homogenous then this is especially the case: if you get 40% across the state and don't have that many big areas where you have concentrated support then its basically impossible for you to get significant representation no matter how you draw the map.
The thing about Maryland is that it's quite the opposite; Republicans on a fair map would probably be a bit overrepresented, even in a pretty Democratic state. They'd be guaranteed a very safe district in the Eastern shore, and likely one in the West too. Plus they'd be liable to get a district or two in southern Maryland or suburban Baltimore, depending on how the map is drawn. The possibility of a 4-4 map in a state where Trump got only a third of the vote...probably a lot of why Democrats are defending gerrymandering even though it's still unconscionable in this case.
