I think what others have posted about serialization, character pieces, or short stories are all ways novels can make sense of the MVP concept of lean. There are also sites such as Wattpad that allow the author to publish as they go and get crowd feedback. They can then rework sections based on how fans react to characters, story arcs, etc.
I definitely can understand the frustration with thinking of the book as a product or business but in some ways it is. I think what is different in how I conceive of a product in this post is that in many ways the product (whether a novel, piece of literature, film, painting, etc.) is never finished. It is always a work in progress, a coming-to-be. I did my graduate work in philosophy and multimedia creative works at the European Graduate School, which took a smattering of filmmakers, philosophers, artists, etc. to come together and produce. I found an interesting commonality in the creative process amongst all of them. That commonality was that inevitably the creative work was produced for someone - the customer, viewer, listener, audience. And in that way creative works are a dialogue with an-other. This is what lean is all about at heart. It is making whatever you are working on a dialogue with someone else and incorporating that feedback into the build-measure learn loop.
I, however, do not think that the two are mutually exclusive and even if you are only concerned with the work as an artistic creation, the relationship between the author and the audience is still important.
I am sorry you had such a bad experience with that boss. I have had similar experiences where bosses treat their employees as resources and not people. Of course there is value to having people in the office but not all the time and your employee's lives matter too.
I hope we see a trend towards organizations with a little more empathy for their communities, employees, and customers. Everyone is happier in this instance and a little hint - you usually make a good profit too. Being an empathetic employer and running a productive company are not mutually exclusive.