From "Everyone ought to be rich" - John Jakob Raskob, an executive at DuPont and Chairman of the Democratic National Committee, August 1929. 

"WE HAVE SCARCELY STARTED 

Now anyone may regret that he or she did not have ten thousand dollars ten years ago and did not put it into General Motors or some other good company-and sigh over a lost opportunity. Anyone who firmly believes that the opportunities are closed and that from now on the country will get worse instead of better is welcome to the opinion and to whatever increment it will bring. I think that we have scarcely started, and I have thought so for many years." 

This was when the average American family made $40/week and he was advocating putting $15/month in the stock market. Two months later the market crashed.

There are parallels you can draw from 1929 to bitcoin today.