Earlier quoted context omitted.
How does this square with regimes like Singapore, which is one of the least corrupt nations in the world yet also an authoritarian, one-party system?
It doesn't because their premise falls apart in democracies too. Civil servants in democracies are not elected and they have the same 'stopping power'. A planning officer in the UK could just as easily decide to arbritrarily block plans they disagree with as in an authoratian country.
At worst the person gets fired and is prohibited from public sector jobs at that tier of government afterwards for a period of time while the story is fresh in peoples minds, in the rare case the plutocratic owned media let's such a story come out of its mass media products about the not-paid-for bureaucratic elements of government in hopes of reducing polarization that comes from over-promoting one of the arbitrarily different parties as a means of providing the commoners what Orwell called "Two Minutes Hate" or a means of obtaining cathartic release from the tensions that making them believe they are somehow co-authors of the government to keep them engaged as willing participants.