We have a proverb in our language which i wanted to translate it word by word it would be "No one buys his art" or "There is no customer for the product which is produced by him". If you want to interpret it, it means that regardless of what service you provide, There is no one who pays for it. Do we have the same or at least similar expression in English ?
There are many possible ways to say it.
Let's look at your example with the word "art":
- His art isn't profitable.
- His art doesn't bring money.
- His art isn't requested.
- There's no demand for his art on the market.