WhatsApp is a Meta business unit, yes.

And it has its own rules and policies for what is shared with other Meta business units.

Google has spell out the same. Just because you provide data like location to one Google service doesn’t automatically mean every other Google service can access it.

And they can’t just change their internal data policies however they like as some of this is governed by legal regulations.

Here’s a a story about how Google is not allowed to share data across business units without user consent, at least in the EU.

https://www.theverge.com/2024/1/12/24036312/google-digital-markets-act-services-user-data-opt-out