They can't- Musk is empowered to fire leaders of agencies that refuse to work with DOGE. It's comply or leave- and if you leave, they will just find a lackey who will comply.
Nobody will help them "hold the line". The damage to them personally would be immense. If you have a family, or any other responsibilities (like your own health and well-being) there's only one wise thing to do: leave.
At the end, only surviving counts.
It's not entitlement, it's doing the right thing for as long as you can.
Probably different for government jobs. They will know if you've been fired from a government job. And once you are institutionalized as a beauracrat it can be hard to work elsewhere. You would basically be restarting your career from scratch.
Congress is a pile of squabbling children and has been at least my entire lifetime.