This is an interesting (and depressing) read though it mirrors things that I've seen.
I have also noticed people that were the experienced elders when I first got involved 15 years ago disappearing over time. I used to wonder where all of the 65 year old magicians were, for example. Now, I think the answer is "hiding from you."
You can ping this entry by using http://www.khephra.org/mt-tb.cgi/470 .