Brokerages do not have a fiduciary duty to prevent customers from losing their money in bad trades. It's one thing to shut down margin trading or even possibly

Brokerages do not have a fiduciary duty to prevent customers from losing their money in bad trades. It's one thing to shut down margin trading or even possibly options purchases, but to not allow people to buy a stock with their own money is pretty bad. There is zero risk to the brokerage there.