That era was still too early for widespread self-hosting and people were barely discovering all that internet tech. So what Jabber/XMPP offered was still neither appealing nor user-friendly enough.

Moreover, it was Whatsapp that fixed your mobile number as your username that ruined Jabber's momentum, not Google. Google Talk or Chat had never reached a notable market share.

Confidential is something which is not meant to be disclosed, but people gossiping call anything as such that has not been yet divulged to the public.