Was it ever actually substantiated? They said the same thing about the "no jokes" policy and there were plenty of jokes in BvS, they just weren't the laugh out loud jokes you'd find in a Marvel film. I can see DC wanting to keep their stuff relatively serious but "grim" is something else entirely.

I don't see why they shouldn't, because to be fair, not every director in DC's corner is Zack Snyder.
Honestly, I'm expecting Suicide Squad to be a surprise and Wonder Woman to be good, and unfortunately we have to wait until 2018 but Ben Affleck's Batman is probably going to be great.

This is what happens when idiots like AVClub overreact to A GUY WEARING LIPSTICK WITH GREENHAIR AND NO ACTUAL MAKEUP JESUS H CHRIST IT'S CLEARLY NOT THE WHOLE COSTUME YOU EFFING MORONS.