I guess the fact that in the age of mobile-first responsive content this guy decides to publish as word-exported-to-pdf tells you everything you need to know about his ideas of "good user experience"
Publishing something in the Portable Document Format (particularly on a non-web subject) is not unacceptable.
HTML is nice, but it does have its drawbacks. For example, HTML doesn't have pagination or standard TOC support. It's hypermedia, so you have to link out to a bunch of other files, making it much more cumbersome to transmit and distribute. Using a zip, I suppose? (Yes, you can use data URIs in HTML5 compliant viewers, for inflated sizes, and mandatory full file reads before rendering.)
I probably wouldn't have done a PDF either, but I think you're reading more into it then you can.
Given the context and content, it's pretty ironic.