You can say that about a lot of languages other than node. How many billion dollar companies have their software written in PHP - a language that many people would agree has far more glaring issues than node.
My point, is that I believe your comments miss the larger picture. There is far more involved with deciding which language to build a product with than "which language is best."
I don't disagree with you about Go being a great language - but for most companies, it is not even remotely practical to use. Hiring talented Go developers is hard because there are so few. Their current employees may or may not know Go, what do you do about that? Etc.
If anything the comment on hiring highlights the use of Node being problematic. It's difficult to write robust systems in Node even as a seasoned Node developer.
Node has its perks but for a money making machine that relies solely on being available and providing a good customer experience, not so much.
I can't imagine the ops nightmares at that size, one buggy code path and the entire cluster could be down. These are issues that drove me away from Node to Go, in my opinion Node has way too many issues to run in money-making scenarios.