This page has the 'Google Groups disease' that's rapidly spreading across Google's services. If you are completely logged-out of Google, you can access it. But let's say you have a login elsewhere with Google - perhaps even one still good enough to retain your search prefs, and offer instant access to other services requiring login. Still, visiting certain other pages, like this one and before it Google Groups 'public' archives, triggers a request to login. Annoying and kind of creepy/bossy: "either reconfirm who you are on demand, even when visiting 'public' pages, or you have to log out of all our services".
You do have to log-in to share/connect to a remote desktop session. It seems to be utilising Google talk gadget (https://talkgadget.google.com/talkgadget/blank), this is probably why it requires a Google account.