I'm not a Go user so I don't really know how to Go proxy works, but if webmasters had a way to opt out via robots.txt or specific status codes (429) and then th

I'm not a Go user so I don't really know how to Go proxy works, but if webmasters had a way to opt out via robots.txt or specific status codes (429) and then the proxy at Google sends a response to the client meaning "try it yourself" (i.e., try again in direct mode) then it could have been an adequate solution for this scenario.