The logic standing behind this feature was replicated from the vanilla and I believe (as the man who discovered it) it was disabled for the reason. I thought it might be "bad consequences", ability to exploit and bait enemies. But now I thing I was wrong. The reason of disabling that is the simple unfinished code. It wasn't properly tested thus they simply disabled it.
The fact is, being working with vanilla logic it makes really the mildest difference. In particular, it works only when aliens dropped their weapon during panic action.
In this form I don't think it even worth bothering. I believe the logic should be updated and expanded to be used in all possible cases, without looking back on possible exploitation and baiting. The alien who does have weapon or grenade doesn't care on other lying weapon. It care only when it's entirely unarmed. And in this case it doesn't even matter baited it or not. If alien was mced and under mc disarmed, why it should worry about baiting? For the God sakes, it was already mind raped. It should take any opportunity even desperate into work!