They built Gmail. People need it desperately. So far, no one distrusts it or has any reason to. That's their identity moat.
To say people don't distrust google/gmail shows your naïveté and/or your rose coloured google glasses.
Search and the collaborative part of google docs (ie multiple concurrent editors on a document) is the only thing where it's hard to find a true competitor that you can self host, not to mention hosted solutions.
Aren't you a charmer.
I'm about as far from a Google fanboy as exists. Trust in this conversation has been about existing tomorrow or not. No one doubts Gmail is going to exist tomorrow.
And while you're right about the very obvious assertion that email existed before Gmail, that misses the point. There's a switching cost involved in changing your email. You have to inform all your contacts, update all of your accounts, learn a new web interface.
It's a damn good moat.
Search is the moat for me. Switching email is not nearly as big of a deal.
Businesses would largely be using their own domains, so the point is moot.
I am sad Google is getting out of this market, since that brings me inconvenience of migration. But I'm sure the niche will be filled in.