In that sense, does it matter? Security look at a steady stream of bags, and whether it is 100 bags generated by 100 people, or 40 doesn't make any difference. IF passengers were trained to be prepared for the 1 bag rule before leaving home, then you could argue a beneficial impact on queuing time (possibly). Other than that leave it to the airlines, who have much more interest in restricting the overall quantity of hand baggage due to the storage/safety constraints in the cabin.