This command is a source of understandable confusion, which we are currently discussing how best to remedy.
What `enpkg epd` does is give you all the package versions that are in the most recent EPD installer, which at the moment is 7.3.2. As such, this command is a relic of slower days. What it does not do is give you the most recent version of all EPD packages. At the moment, that can only be done package-by-package, though we are planning how best to provide global update, and related functionality, both with `enpkg` and with our new GUI package manager (now in beta.)
You can display all outdated packages with `enpkg --whats-new`.