Volatility is usually exploding when left tail risk is materializing during severe crises, such as in 2008 or in March 2020. During times of presumably low risk, when market valuations are skyrocketing, volatility is usually low and thus under-priced.

Thus, buying volatility, when it is under-priced during boom phases, quasi as insurance against left tail risk, in order to sell it at exploded prices, when this risk materializes during deep crises, is quite a smart defensive strategy, originating partly from Taleb.

Thus, with competitive long-volatility trading strategies you can get a kind of insurance that is not only free but can earn you a profit like equities over a whole market cycle, if the Eurekahedge index is a useful index for this alternative return potential.

The price you have to pay for that is the risk that the payout is not a guaranteed hedge of the nominal losses in equity value during the next crisis.