I don't accept such risk management, what if the BTC stay near the $9000 and altcoins start to compete with each other for reaching first to the previous all time high prices. The standards can be destroyed if the market calm is erased with the big news by the governments which are thinking about to resist the Libra project. Adding new promising altcoins to the altcoin portfolio can decrease the risk of dependence from the single altcoin price performance.