"The former Fed employee was recently sentenced to one year of probation and fined $5,000."
So, he mined bitcoin on FED servers for over 2 years and got $5000 fine? I don't know how much mining power that server had, but I'd expect that he mined much more than $5000, so the operation was definitely worth it! Even more so if he held the coins for over 2 years. The banking system is breaking from the inside haha
I assume it was just a regular server system, so I don't think he gained much from it, but since it's free for him personally, every small amount adds up to something decent a few years later. It's nothing new as students also have miners running on their university servers even though it's against the rules. It's basically free money for them as they don't have to invest or maintain hardware at their own cost. It lasts until they get caught.