At Google and many other tech companies, internal machines are configured to have go/<whatever> work just like you describe. Looks like someone even made a whole company around it
I can’t speak for anywhere else, but I’m pretty sure Google uses a Proxy Auto Config script for go links, which should prevent that from happening in most cases.
I have found Chrome more willing to resolve go/foo as a web search. As a result, the Google autocomplete suggestions for terms like "go/m" are pretty amusing
I've never seen a configuration that would set a default subdomain search on .com., so I find this hard to believe. Can you show me a browser that resolves like this?