The author does not work for Microsoft

My bad, it was the PR merger that works for Microsoft, not the author.

nor he did add this field to “other open source projects”

Yes he did. He did several PRs using/collecting that field:

• archlinux/archinstall. This one is for a required field at install, not an optional one.
• canonical/ubuntu-desktop-provision
• another one in the same repo.
• yet another one in the same Canonical repo
• accountsservice

People just love to hate anything systemd related

Agree, and I actually like systemd, but I don't see the relantionship between that and my comment.