The EXACT same arguments can be made about ANY other modification to the vehicle or violating ANY other type of law.
Crash going above the speed limit, uh oh in trouble for speeding
Crash with aftermarket non-DOT bumpers and hurt someone, uh oh in trouble for illegal parts
Crash with illegal tint on the windows, uh oh in trouble for illegal obstruction of vision
Crash with beadlocks on, uh oh in trouble for non-DOT wheels
Crash while towing 200 lbs above your GVWR, uh oh in trouble for exceeding the trucks rating
Crash while buzzed, uh oh in trouble for exceeding your BAC limit
I understand your point. You constantly break all kinds of laws, so what's one more? OK- Got it.
The problem is, your advise on the matter is terrible. When I'm towing a heavy trailer, I don't speed. I don't have illegal tint, bumpers, or wheels on my truck. I also don't drive vehicles when I'm drunk. All your hypotheticals are out the window. The only legal issue I'm concerned about when towing a heavy load is the GVWR and CGVWR.
If I'm in an accident, even if it's not my fault- my insurance company could easily say "you are on your own" if it was overweight. Why would they cover it if they can just as easily be free of all liability?
I don't know if you've seen how much money can be involved in a wreck, but you can top $500,000 very quickly. Throw in a few people's medical bills and it's pushing a $1 million easy. I'd prefer to not throw away everything I've worked for my entire life and go into bankruptcy just because some guy on the internet said it's no big deal to tow a few hundred pounds over the rating of the truck.
In reality, it IS a big deal. For you to act like it's not is a disservice to anyone reading this in the future and the OP who asked.