I'm sorry but I just can't go along with that. We can't just dismiss any changes we don't like with tired old cliches. I have had a long experience in coaching youth rugby and seen far too many serious injuries, including one lad I had coached in the past ending up a quadraplegic at the age of 17. Is that hurt enough for you? If the game doesn't tackle risk head on (pardon the pun) then it will be done for us, and we'll have nobody to blame but ourselves.
As for your unsupported claims for the 6 Nations, on what do you base that? One of the main reasons, in my opinion, for the lowering number of weeks spent out of the game with head and brain injuries is the introduction of Head Injury Assessments, particularly in light of the fact that players are not given an option. Like most, I would often fight to stay on the field of play, and I wasn't often right about that. Every single study, without exception, into the frequency of injuries in the game has found that they have increased significantly since the advent of professionalism, some claiming they have almost doubled. Periods between injuries have at the same time reduced. Simply put, each player will be injured considerably more often. If none of this fails to concern you, then I'm not sure what it will take.