Call option 101: A call option is basically a right (not an obligation) to buy a specific stock at a specific price (strike price) some time in the future. Loss is limited to the premium paid for option and gains are basically unlimited.

If for instance I buy a 2-week NFLX Call option at a $2 premium with a strike price of $545, and in two weeks the price of NFLX is trading at $560 then I would exercise my option to buy 100 NFLX stock at $545 and could immediately sell it for a profit at the market price $560.

A lot of times also, speculators never exercise the option and just close the position by making the opposite bet. (i.e. sell the call option to another investor/speculator rather than buy 100 stock at the strike price)

Thoughts: I think this guy is making a fight against times as well as believing a fallacy that the stock-market 100% correlates with fundamental analysis of the underlying company. Yes P/E is high for many companies, and I have heard of a current "tech-bubble" but who knows. How much is "too much"? No one really does. Bet on the total markets long term and you'll probably be ok. Also buy BTC