But hair-splitting digital privacy may be a lost cause, better perhaps to take up David Brin's position (way back in 1998) that if everyone's everything is out there, we ought to make sure that everyone has access to all of it, maximal equitable transparency
sfpl.bibliocommons.com/v2/record/S9...

On that question (What content of "mine" is Gemini chewing on? And how is it boxed?) here's a handy bunch of fine print, I still think a clear statement to contextualize anxious-making news items would be good but meanwhile there's this:
support.google.com/gemini/answe...

I'd pay extra for "private universal indexing" in Gmail/Google Apps, if it's already a thing Google would do well to let folks know (and/or plainly clarify the scope of what Gemini is digesting), though as I said we're already way down the road on everybody's everything is already out there

I guess it's a bit "that horse already left the barn" to worry about Google training AI libraries accessible outside my own Gmail realm, that's been happening with Google search since forever, also with Meta apps etc, stick with paper and pen if you don't want your goodies to get borrowed