I’ve noticed that in the new beta chat, whenever you enter a chat room you automatically gain points (you’re rating) for simply being there. I had this one venter who continuously kept on going on and off. At first I thought the person had a connection issue until I noticed that his score was going up continuously after 4+ attempts.
Personally, I don’t agree with your rating score being posted up, having how long the person has had the account is more reliable in my opinion. However, the only simple alternative in mind is not allow the score to increase unless 5 minutes or more has elapsed during the chat. Perhaps adding how long the chat duration was to the chat history may also be useful (it only shows when the chat happened/ended).