It's hard to say. A confounding factor is that DILP and RTDE tend to occur in Dark-Is-Good fics at about equal levels, so it would be hard to tell whether it slanted more one way or another.

I think the reason DILP gets ragged on so much more is that people usually don't think the characters in question are canonically RTDEs. ('People who tag Dark![character] usually know they're writing a character as a murderous psychopaths for shits and giggles', is what I mean.)
With DILP, you're much more likely to see people defending the DILP characterizations as Really Canon Under It All. Then again, this may be because most people enjoy defending favorite characters more than they do bashing hated ones, so they simply devote more time to the DILP essays. (Certainly, RTDE essays are all the rage amongst HP fandom - RTDE!Snape amongst some canonfen, RTDE!Ron amongst Harmonians, RTDE!Harry with reason amongst anticanonfen, RTDE!Sirius + RTDE!James (+RTDE!Lily, at times) amongst Snapefen, etc.)