Only some altcoins are scams. But some altcoins like ETH and litecoin are genuine projects. If someone can find genuine projects from newly launched altcoins, he can still make a lot of money with crypto.
Your statement falls horribly short of the reality investors encounter, we have more than 10k altcoins on the market at this moment and I will not be surprised if that number grew to 30k once the bull market is in full effect.
For your statement to be true only a minority of altcoins must be scams, so do you think the majority of those altcoins are actually good projects? You mentioned two coins, could you mention thousands of coins that are just as good as them? I know you cannot do it, no one can as there are not many good altcoins out there and at best there are one hundred coins that could deserve our attention, and I am actually being very generous with that estimate.