I would say that they are not as safe as modern cars and trucks we have today. That being said , I do not believe they are unsafe to drive. That is a blanket statement that is just not true. It might not be the best choice for a new driver, but it also depends on the driver. I have seen teenagers that are very capable of driving these rigs without a problem, I have also seen teen drivers I wouldn't trust with a bicycle.
These rigs can be made a little safer than they were from the factory. Better seat belts, roll cage, etc.
My first vehicle was a 79 Scout I got it my Junior year of High School, I had no problems. My second vehicle was a 76 Bronco, I got it my senior year, I had no problems. I saved and bought my own vehicles and made me appreciate what I had and I got what I liked. I will say that I was your typical teen driver for my day, a little reckless and wild, but I never thought it was a dangerous ride.
I also believe that when its your time its your time. I see people getting hurt everyday that are doing everything in their power to be safe. I also see the other end of the spectrum of people without a care in the world doing dumb things and never facing any consequences for their actions.
I think the political correctness and the fun police are taking things a little too far on many issues and it needs to be tamed down a bit. You only get one shot at life and you should be able to enjoy it the way you want to within reason.
A bit of a rant but I hope it helps. I am sure both sides of this issue will be shared by others.
Good luck and I hope you can change someones mind and get yourself a Bronco!