Life is vast, time is limited, not everyone knows everything, especially when your lifetime is a spec of dust in this universe. No one knows enough to give advice about other's life choices.
You cannot know his conditions, you cannot calculate beforehand what he is going to create. You can only give a probability from a tiny set of observations conceived in your limited skull size, which we all have.
Statistics is good, it tells you about empirical data but we need to set our priorities and red lines right, especially when we affect other's life choices.
Everyone should be able to do what they love, regardless of their chance of success. Otherwise we open the pandoras box by treating humans as goods that can be classified. That is morally corrupt, that is morally disgusting, that is morally pitiful.
I have seen more people that works at respectable fortune companies that could not create shit in 10 years whereas a fresh college graduate could make an amazing app in two months. I have seen people at 14 years old doing unbelievable stuff without any diploma.
Whether giving people false hope is a virtue or not is arbitrary as we do not know ahead of time what this gentlemen might create.
But pretending to know what will happen ahead of time is equivalent of being a charlatan.
live and let people live