Bart came back in Flash War, but the Flashes haven't acknowledged him since. Like, this is a key Flash Family member that's been roundly ignored, I assume because Bendis called dibs. So yeah, this is more of a DC Comics problem. And Tim's been gone since Detective ended, and this is a bit harder to square with how his run there—he didn't want to do the superhero thing anymore—but then he's also met Bart?
It's just... weird.
I'm willing to ignore most of it because Young Justice is back, baby.
I mean, that's pretty much it, right?
I kind of feel like this is the consequence of DC wanting to have their cake and eat it too with Rebirth not fully going back to pre-New 52 continuity.