Why fire so many civil servants?

Bannon and Musk are at odds on how it might happen, but both of them support trump's intention to get rid of the "Deep State," who are non partisan federal workers who do the yeoman's work that makes things happen in government. As a military and civil service veteran, I have seen reductions in force which are essentially consolidation and downsizing. Generally they are orderly and workers are given retirement or buyout options and a reasonable deadline to make their decision. Cutting out tens (or even hundreds) of thousands of jobs at once with an email notice has never happened. trump and musk don't seem to realize or care that these people are consumers with families, mortgages, medical issues/bills, etc.
The Project 2025 folks are already recruiting new hires who will no doubt be expected to sign a loyalty oath to trump. (My oaths were always to the US Constitution; never to the President or to one person). Even some cabinet heads have recently pledged allegiance to trump, partially because they know he can pardon them for illegal acts. Its mostly about power and control via authoritarianism and dictatorship, and the republicans in congress have folded. There will be no cavalry; democrats and other non-MAGATs will have to save ourselves and the country. Buckle up! It's going to be a bumpy ride.