If you are a altcoin investor, do not keep all your eggs in one basket, if you believe in an altcoin, make sure it's not the only one, in fact, the more coins you have in your portfolio the lesser the risk, because not all the coins will go bad or get hacked, if one out of 5 or 10 become successful, 6x to , 10x or more, you've made back your ROI and still have some gains.
Yes, as good as altcoins are, if we trust certain altcoins, not 100%, there must be something called risk and fund management. In this case, it is true that we don't put all our money in just one particular altcoin investment. because the risk is very high. Actually, if you want to lower the risk, we are better off also investing in Bitcoin as the main asset and then investing in altcoins.
risk management honestly means nothing if all the coins we invested in for the sake of diversification are just bunch of shitcoins in general so yea, it's better investing in bitcoin and ethereum.
wanted to add one thing that is diversification doesn't necessarily means equal distribution among the coins we invested but instead always invest heavily in coin that's famous and have massive liquidity like btc and ethereum.