we're on the same path but my point is:
It's up to owners/operators to comply with manufacturers' maximum loads. If someone wants to overload a vehicle due to ignorance/stupidity or arrogance, that's an owner/operator probem NOT the manufacturers'.
Manufacturers have clearly published limits - websites, sales documents and owners manuals. It's usually not too far from Power and Torque outputs which everyone seems to find easily... Yep, for the 200 series, too
Accesories, fuel and and people are loads.
Unfortunately consumer/buyer behaviour is to try 'live the dream' rather than 'buy the reality' and it is only experiecne (often hard-won and expensive experience!) that changes this common trait of human nature.
Every few weeks, it seems, there is someone on here and other web forums bleating about a broken chassis or suspension and saying 'Oh, but I thought my Mighty Boy could carry 4.4 tonnes... after all, it is a ute and it should carry a load... ' Or, 'But the salesman sold it to me, surely it's OK... sob, sob'
Lost - yep that Rodeo/fifth wheeler link (and Commodore pic) is a great example. Ol' Mate probably bought the fifth wheeler on size to impress his mates, and the ute on price because he over-spent on the rig.
Year 5 maths... easy.