You are correct. The example is bad grammar. If he no longer paints, then it should be "painted", past tense.
We commonly describe things like this with the present tense, but with the intent that it is ongoing. "Bob paints very well." Although it is in the present tense, we don't mean that it is only true at this instant right now. It is true now and has been true for some period of time, possibly decades. Exactly what time period is "present" depends on context. If I say, "This rock in my shoe hurts", I probably mean that it hurts at this instant and has been hurting for perhaps a few minutes. Presumably I would not leave a rock in my shoe for days or months -- I'd take it out. But if I say, "The Earth orbits the Sun", that has been true since the Earth and Sun were created.
But when the context indicates that the statement is no longer true -- as it explicitly says here -- than the present does is no longer correct. It should be past.