He has passion. But he can't do this without support.
That's not how it works.
Considering there are hundreds of devs all vying to get our money it gets spread a bit thin.
Out of those hundreds of devs you'll find a handful will make good money from it, a few dozen may be able to make a living. The rest will earn between nothing and 1k a month.
Out of all those devs that are making a living from this, very few of those did so with their first game.
Anyone looking to make adult games and make money is going to fail. There are more and more devs appearing every day but the amount of paying players is barely increasing and those that are around already have games they support.
If a dev wants to make money it's going to take a lot more than a 0.1 and a tale of hardship.
It's the second year of a global pandemic, we're all going through hardships.
If money is his only motivation and not making any with a content bare 0.1 kills that motivation then this isn't the business for him.
With a lot of games getting abandoned, the lack of disposable income and people already having games they support someone expecting money with this is aiming way too high.
Tell him to finish a game first then people may take notice, if he doesn't have it in him then tell him to quit and find a different career.