The problem with this thread is that it assumes that Go will simply die without Google.
While it is true that Go wouldn't have gotten to where it is now without Google's visionaries moving it along, it has certainly picked up enough momentum to continue to thrive on its own.
(Can you even "discontinue" an open source programming language?)
Another problem with this thread is that it's comparing apples to oranges. Go isn't actually a service. Go wouldn't need to drain server resources the way those discontinued services would have done. Most importantly, Go can never become a failed project or a blemish on the company such that it would need to be "pulled" in the first place. Why? Because Go is just too awesome. (That's an opinion, but it's also a fact.)
Besides, Go isn't going anywhere anytime soon. It's not going to just randomly disappear one day. It works. If it ever stops working, we'll fix it, as a community.
Because it's worth it.