Not completely useless, but completely riskier. It is completely difficult to know which altcoins will generate profit for you, and it is also completely difficult to know when the coin can get pumped and dumped. At least for a decade now, Bitcoin has lived, and it's still waxing stronger. It's been defined that Bitcoin has two seasons, which are the bear and bull markets, and during the bull market, investors make some profit on their coins that they have purchased during the bear season. Altcoins mostly get so influenced by the bull season of Bitcoin that some of the altcoins get pumped, and after they dump, there is likely a 0.1% possibility of the token rising again. In fact, you can even buy an altcoin, and the project can decide to do a token swap while you are sleeping ( ), and by the time you wake up, the time frame they gave for the token swap is over, which will give you a total loss of funds.