The 4.0.0-beta.2 README didn't use our fixture but the main README of the jQuery repo:
https://www.npmjs.com/package/jquery/v/4.0.0-beta.2
The fixture was as intended:
https://github.com/jquery/jquery/blob/4.0.0-beta.2/build/fixtures/README.md

There are other issues with this version: it contains the .vscode folder and a local.log file (it looks like it wasn't done on a fresh clone?) and some other files:
https://www.npmjs.com/package/jquery/v/4.0.0-beta.2?activeTab=code

I suspect npm publish was done from the jquery/jquery repo instead of the proper jquery/jquery-dist - that repo has a correct README. We've enabled publishing to npm in the release-it config and release-it doesn't know we intend to publish from a different repository.

Looking at the release-it npm config options, if we have the latest state of jquery-dist in a subfolder during the release, maybe setting npm.publishPath would be enough?