In CHAT when it says Message Content Deleted is that for everyone?

In Chat  re the delete option it clearly says everything is deleted, is that for both parties?

I had a communication recently where it appeared I and the customer had some prior dialogue but I could only see my replies which made no sense as something seemed to be missing?

How does this work?

Thanks

I got a reply on this:

“deleting a chat does not impact the other person. it just removes it from your chat list”

I’m wondering what the value of this is?