I never had the chance to hear "Davy Graham? Bert Jansch? Al Stewart?" in their teenage years but the fact that names such as those stand out from the crowd would indicate that they were in a minority at the time.

Most young folkies at that time were lucky if they could string together more than four or five chords and there were very few good instrumentalists to be heard back then. You had fiddlers like Swarb, Aly Bain and so on but even they were still in the early stages of their careers.

Evidence?

Compare old recordings from that period with what's available now.

Of course, these great musicians have developed and improved over the years but so will those young ones of today.

Also, please note I did say "In general" and, therefore, I didn't mean that the best of today's young musicians were necessarily better than "the best" of previous generations. However, I'd suggest that it is fairly obvious that far more of them have reached a higher standard than back then.