Your question unreservedly assumes that stock market crashes are bad. I will play devil's advocate. I can think of 3 counterarguments.
Stock market crashes are good, — and financially benefit, — bears and short sellers — because then they profit! Particularly those who longed put options on the stocks that crashed!
If the stock market crashes from a speculative bubble or irrational exuberance, then the stock market crash is completely reasonable and not the problem. The "permanently high plateau" (I am quoting Irving Fisher) or bubble was the problem, not the crash which restored and lowered stock prices to sanity, fundamental valuation and accounting values.
A stock market crash can allow investors to buy and long shares of astronomically priced stocks, like FAANG and Tesla. Some brokerages lack the feature of buying fractional shares.