It's a stretch to say /var is for application _user_ data. For a certain value of "user" sure, like MariaDB or Redis. They're "users", and have data in /var but it's a non-interactive session.

User data is stored in the user's $HOME, of which none of those locations are, generally, writable to an end-user, and wouldn't be a place to permanently store that data.

Those aren’t writable for users.