People who are super passionate about making indie games I'm going to do it regardless, so this is good advice.
Of course I agree that if they can do it because it's something they really want to create, and not worry about whether it makes money, then they'll be much better mentally (and financially!) prepared.
I think such advice misunderstands the psychology of why people gamble on very long odds. The primary drive is emotional, not rational. The rational brain only has to be convinced that a theoretical possibility exists. After that, it's a matter of emotional appeal, and culture is very good at presenting seductive narratives based on rare occurrences.
Not 100% successfully, but of course it helps. Why don't you go around and ask some people why they don't play the lottery?
I think such advice misunderstands the psychology of why people gamble on very long odds.
It's why I don't gamble. It's why lots of people don't gamble. People aren't completely rational, but they're not completely irrational either.
Helping people put understand the true odds of what they're engaged in is a good thing.
What do you have against people knowing the facts?
The equivalent of lottery with video games would be spamming app markets with shitty games made in a week-end, hoping it catches up somehow. One day someone will make another Flappy Bird, but it will probably not be you.
Likewise, if you are going to put your heart into something like this... do it because you want to...
if you win? great. but it'll be the exception to the rule.