[lwneal]

I think it's about citation. Traditionally, a pdf is a complete and finished work, analogous to a published journal article or book. It is static content and will not change, unlike HTML which might be "under construction".

This isn't necessarily still true: HTML content can stay up on the web forever and a pdf can change, but people still prefer to cite something that looks like a paper document.

Since a whitepaper is often meant to be cited, it's published as a pdf to take advantage of this preference.

The best approach is to publish a PDF for citation along with a public HTML demo, like https://jonbarron.info/mipnerf360/

[civilitty]

It's also feasible to track changes this way. Download the PDF and compare the md5/crc/sha hash to an older pdf file - if they're the same, then there haven't been any changes.

With web pages, you have to download all the linked files and turn them into a deterministic archive and hope that the Javascript included doesn't pull any dynamic content (which isn't really practical to begin with).

[simonw]

This is a really convincing answer, thank you.