Yes. Like the difference between a logical fallacy and a mistaken premise. One is an error in process, the other is an error in data. I took nonsense to be an implied error in process as it was paired with innumeracy.
Innumeracy is an ignorance of the processes of mathematics, which does not follow from using incorrect data.
So yes, you were using those words incorrectly.
It's possible my assumptions are incorrect, it's even possible they're so far incorrect that my conclusions are incorrect. But just because you think they're insultingly stupid doesn't make them incorrect. It just means you have your own assumptions that differ.
It looks like regular big book PDFs (i.e. not adventure module types) go for 29.99, such as the PHB. I can get the hardcover PHB on amazon for 26.10 right now (as opposed to 49.99 at a hobby store). So my assumption of PDFs and books being similarly priced seems apt, especially considering I could also get used copies for 17.25 where WotC sees 0% of that sale.
As for how many pdfs they are selling, I'm pretty sure we have no way of knowing. Here is my thought process for trying to ballpark it:
I would have assumed the number of pdf sales would be tragically low... except that it is all a part of the DnD Beyond website, and the only way their $146 million dollar deal to buy the site makes sense is if people really are throwing shitloads of money at that site. So my traditional understanding that the price of a pdf is $0 since it is super easy to find them for free online, is probably misplaced. Meaning that people are probably actually buying these pdfs in significant quantities.
I checked and DnD 5e does not provide complimentary pdfs with their physical purchases. I would have bet that most pdfs are a double-dip in sales since in my mind people buy the books first and would get pdfs as luxury items to reference more easily.... buuuut, given the huge presence of 5e on roll20, there probably are a lot more people who are purely digital than the demographic I'm more familiar with back in the 2000's. So maybe WotC are cannibalizing their book sales some with pdfs, but that's more profitable for WotC thanks to the superior profit margins.
So I am given a couple reasons to suspect that they are selling a bunch of these pdfs (#1 the impressive value of their webservice and #2 the very substantial online play demographic), and that's even better than selling books because it makes so much more money in profit per pdf. I did not think this was a really controversial observation. Especially since Amazon seems to devour a lot of their profits to make the book profit margins razor thin.
If you can sell PDFs in place of books, then it beats the piss out of book sales.