I think the main objection was Anduril sponsoring NixCon, because a lot of people see it as the Nix community advertising a miltech company in exchange for money the foundation doesn't necessarily need.
And to clarify above, there was no "contributors of this company" dynamic to the outrage.
"jobs" are things which come and go, not a lot of people are will to burn their personal image for a [potentially] uncaring company. And I'm certainly not one of them either.
