The takeaway is not about love and life lessons, it's about listening to people who are smarter than you when they scream that something is a pyramid scheme.
It's really not. Senior bankers carefully weigh downside risks. Those risks are hedged by retainers (i.e. up-front, non-refundable advisory fees), cross-sales (e.g. management fees from a client's assets in the fund business making up for false starts at equity capital markets) and diversification (e.g. "ARAMCO is a juicy whale, but I'll keep a quarter of my staff working on other prospects").
Junior bankers get less deal diversification, but having worked on a deal of this calibre is nothing to sneeze at. The qualified will have distinguished themselves and earned front seats on future deals.
Furthermore, both senior and junior bankers have salaries, benefits and stock in their company. At quite a few of those firms, buying cryptocurrencies in any meaningful quantity would be reason to question a junior's judgement.