Trying to guess where a falling market will bottom is tricky... No one has a crystal ball, but there are times when it is less risky to have market exposure than others. .
In 2000 it took two plus years to go from top to bottom and in 2008, it took 18 months to go from the top to the bottom (both down 50+ pct). You don't have to determine the magnitude of the drop or guess when it will end. You recognize market deterioration, you take your short position and you manage it.
Downturns such as 1987, the 2000 Dotcom Bust, and the 2008 subprime melt down did not happen overnight. For those who aren't oblivious, in such events, at some point it becomes obvious that metrics are deteriorating - economic indicators turn down, earnings announcement disappointments increase, analyst downgrades and earnings revisions increase, the VIX increases, all beginning long before the crisis becomes acute.
Transitioning to cash or quality debt is something that any experienced investor can achieve. If god forbid one takes off the 'long only' tunnel vision blinders, one can even go short a small position and transition to more short as the market drops further. For investors, let the portfolio’s declining value dictate the transition from long to short (and vice versa).
Trying to guess when a bear will start or end is a fool's errand. React, don’t predict.
If you want to play a drop, I'd suggest taking advantage of the high IV by selling a put spread if you think the drop will reverse or call spread if you think it will continue. That way, even if the market goes sideways for a while, you can still make money.
If IV is high and you want to play a drop, sell bullish call spreads.