Stock valuation is not money. You get money if you sell. The stock is a virtual valuation. You need to sell to make it real. You only lost imagined money.
Stock valuation is an up-to-the-second price for a highly liquid asset that is fungible to cash; a good comparison would be the exchange rate affecting the value of the "cash" in your checking account, which is not actual cash, but rather an IOU for cash. "Imagined money" is not a good way to describe stock valuation.
As many a person who bought bitcoin at 20k will tell you...
Then again, last time I checked bitcoin was on the up trend again.