Earlier quoted context omitted.
Don't privacy and security go hand in hand?
I think the distinction is such that with a private (but not secure) application, the only person getting my data is a malicious actor. With a secure (but not private) application, the only person getting my data is the owner of the code & anyone they are willing to share it with (Governments, Ad-tech, etc.) So if your hard requirement is 'nobody can know anything about what I do with this software' you are correct.…
The only other difference is that computersecurity also protects your computer as a resource say against mining trojans.