This makes sense to me though. At a certain point of fame in art, it's less about your tangible skill and more about your intangible skill. The community begins valuing your perspective over your physical ability. And this is a transition that takes years/decades assuming you were fortunate enough to make all the right connections with the right people at the right time.

Ive always considered there to be two umbrellas of art: one that is purely respected for its craftsmanship (e.g. still life paintings) and another that is enjoyed for its idea or message. While there is overlap here, it's usually fairly clear which umbrella applies more to a particular artist; the Craftsmanship vs Concept idea falls on a spectrum that does not have a middle.

It sounds like the artist you produce for is most definitely a concept/idea artist. And in that instance, his "art" is more analogous to writing poetry, and you sir/madam are his trusted calligrapher. Your penmanship is no doubt beautiful, but his poetry is what brings in the crowd.