I am going to defend the Federal supervisors, because I was one (now retired). Bluntly, they have few tools and no support in most circumstances
Short of workplace violence or imprisonment, there is no easy route for termination of a non-probationary Fed. There are hoops that you cannot believe. We tend to transfer problems rather than push them out of government. Its called “Pass the Trash” and you get really good at spotting it after a while.
The employee can procedure you to death and will if they get an attorney. Appeals, false claims of discrimination, racism, and targeting. I’ve seen it all. It is also very toxic in the workplace. The only real tool out there is to make their home their duty station and require checking in while the system grinds through it slowly. Oh, you cannot require the person to work at home either. Note this is just for the professional ranks, its worse if they are union.
Finally senior management will blame you for the issue and for making the organization look bad. I took over a group and was briefed on the way in that person X was a problem. I looked into it, they were not a problem, they were criminal. Went to my boss who told me to follow the system. I did. Brought in the outside authorities. Boss later claimed I blind sided him. Good thing I had the emails.
Not excusing this, but given the system as it is today, it is the only option out there. Its the equivalent of the rubber room used for teachers and cops in large cities. Kind of glad I retired and have all of it behind me.
When I was in the USAF, I had the misfortune to be stationed at Kelly AFB in San Antonio, TX. There, the union force was just about in control of the base. They had generations of family working the union jobs and the base commander literally had to clear personnel decisions through them.
I was given a problem employee as an administrative assistant. I knew about her past problems and the fact that I was just the latest to receive her in their quest to shovel the problem around. I told them I would deal with the problem as it should have been dealt with long ago. I was a lowly 1Lt at the time.
I had numerous meetings with the employee and the appropriate personnel offices to make sure I did everything by the book. It took a year of documentation but I was finally ready to be done with the whole affair... when “leadership” reached in and transferred her across the base. That was the end of it for me but I’m sure she is still there and will eventually receive a fat pension for her “service.”
“Leadership” has no guts to do what is right. When they see someone further down the food chain actually doing the right thing, they are either punished or removed from the situation. Sad.