As someone who does understand how key parts of an industry (i.e., publishing) work, authors broadly fall into one of two camps:

(1) Authors who let other people do all the "non-writing" work, whether via traditional publishing or, if they're self-publishing, paying contractors to do that work. This is both editorial work and, most important for this discussion, layout work. These folks aren't going to use Pollen, but a vanishingly small number of them are going to use anything but a standard word processor. If they get nerdy, they're getting nerdy with Scrivener.

(2) Authors who, for whatever reason, do in fact want to do the layout work themselves. (That group can be subdivided into "people capable of doing the layout" and "people who believe they are capable of doing the layout but really aren't.") They're going to use whatever the hell they feel like using, within whatever constraints are set by whoever they're working with.

In either case, whoever is doing the actual layout is doing it with actual layout tools: at most non-technical publishers this is going to be Adobe InDesign or Quark Xpress; at tech publishers it's at least as likely to be Framemaker. (In my observations LaTeX rarely shows up unless the author is in the "do the layout myself" group.) In either case, Pollen is aimed at the people doing the layout.

And, since you like being harsh, there's no indication you put the least bit of effort into understanding what Pollen's author understands about publishing, typesetting, or anything else. There are valid criticisms to be made of Pollen, starting with the premise that books "on the web" are something that the majority of readers actually want (and the corollary assumptions like "ebook readers can't do as good a job," which is true only to the degree that current ebook readers/creation software can't do so), but "this guy has no idea what he's talking about, he just wanted to write a command line app in Racket" is not one of them.