The speaker says he studied Thai painting but found that the market he could reach responded to a different kind of art. He combined Thai painting elements with international painting styles and talks about selling his work. The key point is how he adapted the presentation of his skills to buyers in his own experience.
What this example can and cannot show
The story does not prove that Thai art has no market or that everyone must change styles to sell work. Decisions depend on an artist's style, customers, costs and goals.
Because this is a short personal account, the article records the experience rather than presenting a general guide to earning income from art.