If you consider one of the reasons for RID was to identify drone operators from flying in places where they are not supposed to be, then the weight is almost irrelevant.
If first responders are prevented from landing an evacuation helicopter...
All I could reply to that is "duh".
Just as it's more likely that a sub 200 gram drone would have the potential to cause less damage than a post 200 gram drone.
Neither of which would or should have a bearing on whether or not RID would be...