That's exactly what I think! If you see before Brave Brothers productions 4minute always had good physical album sales (HUH: 23k, Volume Up: 57k), and after he produced songs for them its sales didn't reach 20k and 'Crazy', the last one produced by others, sold about 21k until today. I really don't care about sales because there are so many good groups that don't sell anything, but in this perspective you can analyze the approval considering they're a famous group and with a well-known fandom.
I'm not saying it'll happen to T-ara, only about perspective approval.