Yep, true. Anyone who uses all their powder today is taking a big risk.
On the other hand, there may be opportunities today. I sold some positions out a few weeks ago, anticipating further falls. Today might be time for me to get back in - even if they then drop further, I will have still got more shares for the same money. And long term would still gain.
But I’ll definitely not be going on a buying spree, and keeping a healthy cash reserve in anticipation of further drops. I fully expect to end up missing the absolutely bottom (most do), but would aim to be catching at least near the bottom or before it’s climbing up too much again (though with the latter, there’s always the dead cat bounce risk).
tl;dr, investing is tricky, timing is impossible, looking at the long term is best even if the short term suffers some.