Do they really have write access though?
So far the only evidence of that is a wired article [1] with anonymous sources, even those source were not 100% sure about it.
Since then wired has posted another article [2] claiming the access have been revoked after announcements from senior officials, which again is from anonymous sources.
I'm really skeptical of these anonymous sources tbh.
[1] https://www.wired.com/story/elon-musk-associate-bfs-federal-...
[2] https://www.wired.com/story/treasury-department-doge-marko-e...
You don't need read-write access for auditing. You don't need root/admin-level privileges.