There's also a school of thought that would try and keep actual load to a percentage of rated payload, such as 80%.
Also, you'd want to de-rate the payload when you replace the anemic tires that the LC comes with larger diameter ones.
Happy overlanding!
Not a vehicle engineer, but a mechanical engineer in unrelated industry. Usually we design and buy designs that have "ratings" knowing they can far far exceed that in practice. The safety factor on piping materials can be a 2 or even 3. I would never think to de-rate something like payload.