I see what you are saying. But the help page basically describes the steps to install a chrome extension. It doesn't say that this extension is specifically prevented from syncing like other extensions. It mentions an authorization dialogue on first run, but it is unclear whether that is the first run per account or the first run per installation of the extension.
I would actually lean towards the latter, as it is in line with extension syncing behavior I have seen in the past. Usually when I am on a new setup of Chrome, and extensions sync and install, they do pop up some sort of installation or setup window notifying you.
Why are we guessing when you can just install Chrome Remote Desktop and try it out?
I've used Chrome Remote Desktop, and the speculation in this thread about automatic extension sync is absolutely baseless: you need someone at the keyboard to actually install the remote desktop features, the extension by itself is not enough.
Is this really the state of HN discussion? It's great that a Google engineer was able to chime in and dispel the wild fears (thanks Sergey), but it shouldn't have been necessary in the first place.
Is the user prompted to understand how the extension can affect them, when it was installed, and where it is syncing from?
To put it another way: if I am a regular end-user and Chrome pops up a dialog asking me to allow the official sounding "Google Remote Desktop App", then why wouldn't I? That doesn't sound scary at all - it's from Google!