Agree. In addition, there are also plenty of artists who either shipped yet died poor (van Gogh, for example) or who were prolific proposers/thinkers/sketchers with "low actual ship rate" (Leonardo never built his helicopter, yet "dreamed in drawing" about it a lot).
Measuring the "influence" of an artist my "number of artworks created and sold" is a bit like measuring academics by "number of papers published". It's at best a very coarse approximation of "the real thing". At worst, total bull.
That’s two hits: the Hobbit and The Lord of the Rings. Also several academic pieces in his professional field. Not including the material subsequently published by his son and estate.
Back in the day, it only took one hit, and after that one could drive off of Skyline Blvd in a sports car, or retire to a horse farm, or run a SF nightclub, etc.
A clear counter example would be someone like Franz Kafka. He hid much of his works in his lifetime, and willed for them to be destroyed posthumously whether published or unpublished.
That anything came down from him was the executors of his will ignoring his stated intent.
And yet he's considered a literary Great of the 20st century.