Art times like this whereas its market value is falling, surely, it is a stupid decision especially if you are aiming for huge profit. Selling will just cust your losses in the mean time but will also cut your profit permanently. Investing would be a way more better option than selling which would somehow help the demand to increase by holding and investing.
Precisely, selling isn't bad but it only became a thing if you sell at wrong date or situation just like we had now. Market value is falling hence selling your funds will be just in vain because instead of getting a profit maybe you'll only get a small portion of it. In this sitaution, it is better for us to hold and wait until market goes up again before make any move, patience is the key for now.