I can personally attest to the value of negotiation. I was recently able to negotiate an additional
$50k/year in cash + RSUs at a BigCo. All it took was three phone/email conversations over two weeks. Before that, I got an improvement of
$10k/year in options with a single email. It has nothing to do with code or my ability to contribute, but negotiating is one of the highest ROI activities I have ever done, despite objectively sucking at it!