With due respect, certainly there is something to be said about having a bit more energy when you are younger, there is also something to be said about a lot of that energy can be used to convince yourself that doing something is far less risky than it actually is.

I've been an active member of this forum since I was in my early 20s (I'm only 30 now) so its not like you are getting advice only from one age group. I can certainly tell you that I have done a few trips where I've done things that I wouldn't recommend now, driving all day, setting up camp, and "seeing" a city by driving through, maybe walking around for a few minutes, and then continuing on. However, I knew at the time that those trips were as much about spending time with friends as they were seeing anything, which is very much I said that if you don't mind driving all day that your trip was possible. But I also recognized that trying to drive 800 miles a day, day in and day out, wasn't a good idea. I probably underestimated the dangers, but certainly it didn't take long to figure out the "fun" factor was seriously hurt by trying to push too hard. Many people who haven't been on a roadtrip don't know this and don't know what reasonable limits are and often try to do more than what is reasonable or even physically possible.

The other fact is when your are younger, you are more likely to take risks and not appreciate how dangerous something can be. Driving tired is a one of the biggest dangers you can face on a roadtrip, but its also one of the most underappreciated dangers out there too. The simple fact is, no matter what your age, the human body can only do so much, and ignoring that can and often does lead to tragic results. That's the very reason why professional drivers have strict limits on how much they can drive in a day. Certainly no one here can stop anyone from driving too much in a day, just like no one here can stop anyone from driving after drinking too much, but that doesn't mean we're going to stop warning of the dangers when people are talking about engaging in risky behavior.