From my experience in the health care field... I think that most PNs today, in younger people are vaccine/viral induced or drug induced.

I remember when the only patients I saw were old who had PN. So in the minds of many PN is an old person's disease. It accompanied diabetes which is now much more common too. Now it is everywhere. As our environment gets more and more toxic, so will the numbers of people increase with PN. The peripheral nerves are very fragile and often the first to react to toxic and infectious assault. I also think alcohol is very over stated. There are many people who were severe alcoholics who never had PN. The ones that are nutritionally compromised are the ones most likely to develop it.

When a disease like MS or PD strikes a young person...that is when people pay attention IMO. MJ Fox was very young when his PD started for example. So was Annette Funicello when she developed MS. Andy Griffiths however was much older, so we don't hear about him, except from within the PN community.
We don't pay much attention to old people in our culture...I am finding that out the hard painful way myself!