This is correct. GP hid a lot of unfounded and speculative negativity behind "this is a signal I'm getting". Not only did Yegge interview at Amazon, he also interviewed at Google and was very successful at senior levels of engineering leadership for the better part of a decade in both roles.

As for imposter syndrome: Yegge graduated from high school at 14 and studied nuclear reactor engineering with the US Navy in addition to his roles at prominent Silicon Valley companies. He is not my pick for somebody with imposter syndrome.

I am a fan of his because I've been reading his blog since the Stevie's Drunken Blog Rants days, and he was quite active in the Emacs community for some time. I also worked at Amazon and so his experience there became particularly interesting to me during that time.