This is presumably why Facebook bought it in the first place, though. They don't need to see anyone's message content for this. They get all the info they need the first time you use it; confirming phone number 123-456-7890 belongs to person@domain.com, so they can tie together your facebook usage with whatever customer surveys, browsing etc you've done. I don't see this as remotely altered by the recent encryption work, other than the latter will entice more people to use the app.

And I think that's really the messaging that needs to have some PR light shed upon. Facebook has access to the meta and contact data (confirmation, Moxie?). For all the hoopla over WhatsApp E2E crypto, users shouldn't forget that they may be handing over phone number, contact data and other meta to the largest ad-tech platform with a real name policy.