This kind of federal regulation had not happened before March 1929. Wall Street was afraid that if this happened, people
would not be able to borrow money to buy stocks, and then no
one could buy the RCA stock that speculators were trying to
sell quickly. This led to the Crash because it made stock brokers
nervous that the government was going to clamp down on
speculation, and they were more ready than ever before to
launch a massive sell-off of stocks if that happened.