That's a fair point if you're assessing something at a particular point in time. So yes at this very moment his portfolio has earned less, because it's more risky. Savings accounts don't have zero risk though, it's just incredibly minimal. Otherwise tell that to the poor sods in the GFC who had their banks collapse!
In the UK savings are protected by the state up to £85k per bank. Still not absolutely zero risk technically I suppose, because theoretically the state could fail to fulfill that guarantee, but effectively it is.