By buying a "put" he is wagering that the price will fall.
The more the market crashes, the higher the value of the put.
The more the market crashes, the higher the value of the put.
VIX (https://finance.yahoo.com/quote/%5EVIX) was at 14-15 just a month ago and now at 65 - one of the highest ever! What a time to be alive after years of suppressed volatility!
Both calls and puts increase in value when volatility increases.