Yeah... the Google search engine is not written in Go. There's a big difference between folks who really, deeply care about sub-ms level latencies ( like this guy https://www.youtube.com/watch?v=S9twUcX1Zp0 ) are not the same folks pushing Go.
Except they are running their downloads site and much of YouTube on Go, among many others. Indexing the world's content may not be smart to write in Go, but Google's other properties are also heavily hit and seem to run fine.
Go is brilliant for faceless fast-response highly-concurrent situations - like APIs and the like.
It's also absurd to accuse Google of not caring about performance when they can search the wealth of information on the Internet in milliseconds.