It’s not really in either Meta or Google’s interests to share that data. What they do is to build super detailed profiles of you and what you’re likely to click on, so they can charge more money for ad impressions.

Meta certainly shares the data internally. https://www.techradar.com/computing/cyber-security/facebooks...

LLMs add a new thread model. If trained on your data, they might very well leak some of its information in some future chat.

Meta, Alphabet might not want that, but it is impossible to completely avoid with current architectures.

Honestly, there are plenty of more profitable things to do with such information. I think ad impressions being the sole motivator for anybody, is sorta two decades ago.

Big companies can negotiate their own terms and enforce them with meaningful legal action.