At our book study people did often ask for clarification of a point and it was answered. We also did occasionally go off topic. But in general the meetings are for answering the questions posed not for requesting information. In fact they timing and structure means that there is no time to elaborate on points or use things in answers that are not in the paragraph. They have done the same with assembly talks by making them shorter there are no fancy introductions or illustrations just a barrage of scripture and misapplication.
The classic example of this is after the oral review the brother always asks if anyone wants any of the answers clarified, on the few occasions where someone has asked for clarification on a question the brother merely reads direct from the preprepared answer given by the WTBTS.
If you ask elders a question they refer you back to the WT publications. If you are a persistent questioner then you get councel.
Also no one does it at the kingdom hall so new ones don't want to look stupid so they don't do it either. There is no culture of questioning within the organisation. In fairness I don't think many people stand up during church services and ask the vicar questions there either. The only place where a new person can ask questions is at their Bible study. At that time they are being fed the bland public face of the WTBTS so questions can be dodged fairly easily with general platitudes.