I find that claim rather ironic, because I feel like the primary reason that PDFs are "unfit for human consumption" is a formatting issue, not as much a technic

I find that claim rather ironic, because I feel like the primary reason that PDFs are "unfit for human consumption" is a formatting issue, not as much a technical or practical issue. The reason they are unfit to read on line is that they are formatted using past formatting standards that are meant for print … not inline reading. There are of course some technical limitations to PDF that would prevent them from being mad "digital first", but even just changing page layout and adjusting margins and spacing and font for horizontal display (as most of our screens are) vs vertical layout as one would read a printed sheet of paper, would make huge differences. I for one actually compensate for that in that I have a dedicated monitor that is vertically oriented in order to read PDF documents. Better yet if you can do it on a very high dpi screen. But even that is not ideal because although I actually like print formats, standards, and conventions (like margins, spacing, and structure), it's simply not relevant or applicable in digital until we get A4/Letter formatted tablets or desktop screens that emulate physical paper … albeit even that, inadequately. Nothing can really replace the advantages of paper, at least not until we get paper thin displays that have zero measurable response times on pen inputs … i.e., likely never.