i'm curious what makes you say it is not up to his usual high standards and not as good as the other books.
i will admit that i was meh on it the first time i read it, but ... on reread, i loved it; it's a great meditation on the nature of art and creation. i think it works better if you think of it as story that hoid is telling, like a long form version of one of his stories embedded in the stormlight books.