>Still not a great precedent, though.

Doesn't desktop Outlook client allow MS to train their AI on your emails? Even if you use GMail in Outlook MS has access to it?

Outlook.com sends links in emails to bing. Meaning your password reset mail links can be indexed. So the AI training seems like the least of their problems...

It does no such thing. What it does do is send those links through safelinks and link preview services.

And yet they end up on bing.com somehow. This has happened to me and I have had to write special code to hard block bing by looking at the user agent. This is a real problem that I have faced personally. This is not a rumor.

With the new Outlook client, all your emails and email account credentials go trough Microsoft's servers, even if you use a 3rd party email provider.[1]

[1] https://news.ycombinator.com/item?id=38208797

Today, as a testing of waters against public opinion. If there is no tidal wave of outrage, expect it everywhere.