Hey, everyone complaining about the title of September's All-Flash #1, there's a reason they did that.
Its historical. In the 40s, Jay Garrick shared the spotlight with several other characters in Flash Comics. He'd get a story, and then a few other characters would each issue. When he got popular enough, they gave him his own quarterly special called All-Flash Quarterly because it was all Flash stories.
Still a dumb name, yes, but its historically dumb and that's what DC Comics specializes in.