And this is ultimately what it comes down to. DC's over reliance on Batman that has only gotten worse over the years since the 80s and I feel like they have only just started to course correct in the last 5 years has led to much of their universe being criminally under utilized.
Look at how long it took to get major projects starring Wonder Woman and Aquaman - classic Justice League characters with years of stories and that are iconic to mainstream audiences - off the ground? When even Superman struggles to get any shine, what chances do characters like Vixen have?
Because let's be clear, characters don't become iconic off the backs of comics alone anymore. Not enough people read them. Storm, Static, John Stewart, and Cyborg reached the status they have off the back of cartoons and movies. Black Panther is an exception, but that's largely because he's been around so long and was pushed as Marvel's premiere Black superhero. And even then, he would never be enjoying his current status were not for the film.
DC is run by people who have no faith in their characters or universe. Not even their white superheroes outside of those who live in Gotham. From the late 90s to the 2000s, they did a lot of work creating new characters and trying to update their universe. However, it doesn't mean shyt when the people in charge either A. only want the universe to look like it did when they were kids or B. have no faith in the DC universe as a concept outside of Batman.
There's also the second Power Girl, but idk what's going on with her atm.