This doesn't work when it comes to cryptocurrencies. People often read about diversification and apply this to cryptocurrencies but they're buying the same exact thing. Selling your bitcoin to diversify into ETH and XRP is like selling a hard asset like gold, valuable art, or your house to buy a penny stock. It's not diversifying, it's gambling!
All cryptocurrencies depend on bitcoin so if you hold bitcoin and something else expect that something to drop more when bitcoin goes down.