Chris,
Every single accident and insurance claim are different and we have no idea what your individual circumstance was.
The fact here is you are giving bad advice to anyone who reads this thread and possibly creating false expectations that will cause someone grief!
An insurance company is not going to replace a truck or car because it is damaged and the owner "demands" a replacement. It simply does not happen.
An insurance company is required by contract to do only what their policy, the insurance regulators of the state, standard insurance industry practices, and the law require. Demands by petulant claimants are not one of their concerns.
In this situation the repair shop prepared a repair estimate that will apparently exceed the treshhold for declaring it a total. If the repair estimate is less, that is all an insurance company is required to pay and all they will pay.
No claimant has a legitimate claim for a replacement truck or car just because he wants it or "demands" it.