An “activated” or “activated default” project is a virtual environment (in your AppData folder), so it’s easy to delete manually without impacting anyone else on the system.
The “state clean” command can be used to clean up activated projects unless you “deployed” them. Deployed projects are neither “Installed” in the traditional sense, nor activated in the usual sense because they are detached.
\https://docs.activestate.com/platform/state/commands/#utilities
The “state clean uninstall” will have also removed the State Tool, so naturally it won’t be useful for any further removals. At this point, you’re probably best off to manually delete the Perl folder and use RegEdit to clean up any registry entries. (Discussion here, for similar case with installed Python)