Feel-good rallying cries like this make for cheap virtue points but are completely meaningless in a reality where pretty much nothing is a binary choice with a low number of variables.
For example, it's easy to sit in an air-conditioned office and say "thou shalt not overload the trucks" but when you actually drag your ass to somewhere you can observe the conditions in which the per-load work is being done it becomes clear that much analysis must be done to figure out if more trucks at 80k is in fact safer than fewer trucks at 120k.
Being that braking distance will increase around 250ft at 65mph I would say it makes a pretty massive difference. That is unless you want to limit the 120k LB truck to 55mph which causes its own issues.
For example, it's easy to sit in an air-conditioned office and say "thou shalt not overload the trucks" but when you actually drag your ass to somewhere you can observe the conditions in which the per-load work is being done it becomes clear that much analysis must be done to figure out if more trucks at 80k is in fact safer than fewer trucks at 120k.