I wonder if Google will be pushing end-to-end email encryption? They have already had some experiments on it.
They have the majority browser, they have the lions share of email hosting. It they played their cards right, they could claim the entire email ecosystem, except for the small portion who won't use Google products on principle. The questions would be would 3rd party clients be allowed, and how would Apple fight it.
Or maybe this is all just a smoke screen to sucker dumb corps. In the existing architecture, your emails still need to be scanned so they can be indexed for search. You could get the same result scanning these indexes as scanning the emails themselves, so from a privacy perspective it could be a non-event.