The issue isn’t whether or not their names are public.
The issue is that Elon Musk is highlighting them specifically in a negative way that will lead to very predictable, very personal, very negative outcomes without any recourse.
It depends if you think there's a difference between a self-formed likely illegal group, doing likely illegal things for ideological purposes getting reported on by a reputable news source, and a civil servant who has been doing their assigned job getting picked on personally and publicly by one of the most powerful people in America who owns the media site he is using to attack them.
I see those as different in reality. We can argue that semantically they can get twisted around as the same thing (government employees getting publicly named in a critical way), but that ignores extremely relevant real-world circumstances.
So, to be clear, I do think "who people in government are and what they do" is appropriately public record.
But yes, there is a difference between media reporting on what high-level government officials are doing and government (or quasi-government) officials singling out low level employees for ridicule. It's the difference between punching up and punching down.
But this is not among the worst things Musk is doing, and if it were a right-wing magazine doing reporting on employees in the federal government rather than someone using their role within the government itself to do it, I might find it distasteful but would have no real qualms about it.