Hoses and belts as the OP appreciates is based on age and not miles driven. Same applies to changing out the coolant and the motor oil and even the transmission fluid.
I change out hoses and belts every 5 years at a minimum. Belts can slip and cause problems long before they break. Radiator hoses can also fatigue and the intake hose can start to collapse and restrict the flow of coolant through the radiator and reduce the lubrication for the water pump.
I see it as penny wise and pound foolish to wait until hoses and belts fail and I am stuck out on the highway. At a bare minimum I would want to have a spare set shrink wrapped and in the truck if I was going to push my luck. For the relatively minor expense involved I see no reason to push this type of maintenance out for any of our vehicles and when used as a tow vehicle this is a great deal more important as getting a tow becomes a much more difficult and expensive proposition in every way.