I don't think this is accurate. The majority of scrums at every level lead either to possession for the team with the put-in, or a penalty in their favour. If the weaker team has the put-in, they can pretty much roll the ball straight back to the number 8 and get it away (possibly not in the rules but completely never policed).

It's exciting when either side gets a shove on and that there's at least the possibility to win one against the head, but I agree the game wouldn't lose that much for anyone but the purists and the front row specialists if we just moved to uncontested scrums.