Likely a mixture of these answers, though if you want to wait for an expert to weigh in maybe ask for that. A roadway is obviously a very different environment with a lot of money and research put into ensuring it can handle a lot of traffic and weight, having to accommodate worst case scenarios so it’s obviously going to have a very strong base, and a comparitively very durable and thick base of asphalt. Your driveway, on the other hand, is probably going to be covered in a mixture very much driven by price. If you do the minimum underlayment and thickness, you’re probably going to need to give it every advantage possible to avoid rework.