I've also been told learning too much about linux or the nuclear reactions in power plants or bombs puts you on a list. I just assume I'm on several.
Whatever you do, don't broadcast on the airwaves, as in pirate radio. That really does put you on the list.
I don't believe they have the people to monitor those that know 'how to use grep' and put them on a list. It stands to no reason, government civil servants are rarely from the top drawer.
Learning too much about Linux puts you on a list? That can't be a thing. Isn't Linux itself entirely a civilian project?