Yeah I got to agree with Robotman here, it’s more a strike against readers when it comes down to it. Because DC has tried new characters in the past, new teams, or even revamping some older properties they have into fresh new ideas. And unfortunately sometimes they just don’t sell, heck there are a couple of long lasting characters who have problems selling (when was the last Firestorm book exactly)
Sometimes it’s a little hard to sell characters like Sideways, Brimstone, Silencer, Talon, Telos, Pandora, Naomi, and etc. when we fall back on the old standbys or maybe we just aren’t interested enough to sustain the book. I know I’m not interested in every little new character dc announces. Heck if I want something new and exciting I’ll just go to an indie publisher who can do whatever they want.
Sometimes it’s even hard for new legacy characters carrying on the name, such as one of my recent favorite Khalid Nassour as Dr. Fate who got an ongoing was lucky to be carried on in Justice League Dark and proceeding books. So yeah it’s a little hard to say DC has stopped trying and maybe more like they don’t do something often that hasn’t been a big success for them.