And you don't need to compare Bitcoin or altcoins with stocks, they are different. Bitcoin and altcoins are volatile, the values change significantly. While stocks price changes seem not too significant and can be easier to predict. With the different in nature, the market characteristics should be a bit different.
But maybe he should invest in bitcoin and not focus on altcoins because that could confuse him even more. But that's up to him because the final decision is in his hands. We can only give him advice.