Also - it's completely free open access, but you can also buy a copy here if you like spending money: https://mitpress.mit.edu/9780262548182/tor/
Why are the PDFs individually watermarked?
It seems antithetical to the spirit of releasing a book about Tor and "future of privacy", and to then not only watermark each PDF, but to not explicitly state that this is the case, let alone explain why.
Can PDFs be crafted such that they would ping remote servers when opened in most PDF viewers?
It's thankfully licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0, which allows for converting the content to other formats (given attribution and non-commercial use, same license, etc etc) [0]. I'd reckon that making a de-fingerprinted version and redistributing it as an epub, md, or pdf again would be allowed, then.
As for getting a clean copy to work from, using Tor would be quite fitting. I plan to convert the version I downloaded to epub for ereader use, maybe downloading it a couple times over different routes and combining to see if that has any impact on the fingerprinting. I'll comment with a download if I get to that and feel it's of a quality worth sharing.
0: https://creativecommons.org/licenses/by-nc-nd/4.0/deed.en#re...