In my opinion, linkedin answers were far better than the groups. Groups are easy to start but hard to maintain and keep engaged. I have learnt that the best way to keep audience focussed is to give specifics which answers can do better than a group. For example, creating a group called "Python developers" might attract a few folks but what do you do when you join it ? A more specific question like "What technology stack is used by python developers for web" will definitely attract a more engaged conversation.