Agreed, Obama used executive power to massively increase the size of agencies so why can’t it be used to reduce them? The president has total legal power to control a lot of the daily care and feeding of govt agencies. Trump could probably start deeming lots of staff non essential. Then start laying off many people. Once done, the empty buildings are simply no longer needed and can be sold!
A lot of those federal employees belong to unions that would strike and REALLY shut down the government — nobody to send out SS checks, process Medicare forms, etc.
The hullabaloo would be horrible. We aren’t talking about a few thousand air traffic controllers like Reagan fired, we are talking about hundreds of thousands of federal workers that will stand together.
If it were me, I would relocate offices across the country to undesirable places like small towns in Alaska and transfer employees to the new office. When they quit rather than transfer, don’t hire anyone to replace them at the new office. You just need good reasons, like cost savings in a small town vs. DC, to prevent union cries that the purpose was to get rid of workers.