Well this was advice my father (an academic and lifelong straight ticket Democrat) gave me decades ago. So it was nothing specific to the current administration.

The difference is that the people affected by whim were, by design, only supposed to be the political appointees, not the civil service rank and file. Those jobs existed for as long as Congress decided that they produced useful results for the American people. Positions could be eliminated by virtue of Congress deciding that a shift in policy was needed, eg fewer Kremlinologists after 1989, but that is not a whim, that is a result of debate.

The current administration is making all positions political, and in doing so, performing an end run around the legislative branch.