Yes of course alt coin can be kept, but we need to be 100% sure that it is sustainable and stable. Because the new coins are uncertain, they can disappear at any time. You definitely don't want to invest in something that is full of high risk. I see that due to the highest faithfulness of the coin, most investors invest in Bitcoin. And the reason for this fidelity is that it does not suddenly dump. The coins at the top of alt coin are also very high fidelity. For example: ETH, BNB, SOL, DOGE, TRX, SHIB, TON, also many more trusted coins come that don't dump suddenly. These coins pump a lot in bull runs. So I would say if you invest in alt coin then invest in these top sustainable coins. They are less risky.