This statement is true for shitcoins provided you make profit from such coin already, but losses are likely, but profit can be by chance, then Suh person should sell the shitcoins and buy bitcoin because the statement is not true for bitcoin, nothing like regret, you will gain. If the price fall, do not sell but just hold and the price will increase back and ready ATH, then no regret. But some people may want to sell for some good reasons, maybe this can apply to them, but there is nothing bad to always hold bitcoin.