And I guess WB has a history of doing this. Back in the 90s they supposedly cancelled Animaniacs and Pinky and the Brain because they were popular with the wrong demographic, only instead of girls it was older, probably college aged viewers.
Pinky and the Brain they kinda knew they had an adult demographic and that's why the first season of the show was sitcom-y. So they could put it in prime time, but it failed against 60 Minutes. Freakazoid was a bigger example of older demos hurting the series, since it was pretty much made
for an older audience, even by accident. Considering the fact the original concept was a toyetic super hero that made Spider-Man level snarky comments (as if Spider-Man didn't have his own cartoon at the time), and it turned into delightful nonsense that little kids couldn't appreciate. Heck, the fact that the Steven Spielberg/Warner Bros cartoons were appealing to adults went back as far as the pilot for Tiny Toons where Buster name checked the "Short weird guys with bad hair."
I'd say the problem with most modern super hero cartoons is that they're in this kinda unfair box where they have to appeal to adult comic fans
and be kid friendly, and it either falls one way or the other. All the crap the Marvel cartoons undeservedly get, their popularity stems from them being just kid friendly enough. Heck, Batman Brave and the Bold got crap for
not being a Timmiverse version of the character, and then fans loving it anyway. And I remember people whining about how Spectacular Spider-Man wasn't the 90's series and dared to have the look of a 2000 era cartoon, only for it to be the
definitive Spider-Man show to the point anything beyond it can't be allowed to flourish.
Of course, I love how TTG is somehow more kid appeal than the other DCU cartoons when they do nothing but make 80's references kids won't get and shove in social satire they'd scratch their heads over. Somehow detailed romantic subplots and grey morality is less appealing to kids than an allegory for colleges screwing students out of money they won't get.