What are the issues with the new TOS? I heard merging data with facebook but couldn’t find a clear summary in the other HN threads. I don’t really use whatsapp

What are the issues with the new TOS? I heard merging data with facebook but couldn’t find a clear summary in the other HN threads. I don’t really use whatsapp now but I have a lot of convo history there. And I also use FB messenger/instagram dm’s, but not for important chats. In that context, is keeping whatsapp for the old message history basically fine? I wouldn’t use it for a new important chat going forward.