The West seems to define "democracy" in a very specific form: there MUST be multiple competing political parties and power MUST, at least in theory (compare Singapore, Mexico, etc) regularly transfer between them as the result of elections.

This is something Western states have been able to pull off, but it's actually sort of peripheral to the theoretical INTENT of democracy-- that the government serves the masses. Good governance is pretty much a by-product of the fear of being voted out of office.

You can, and often do, have the all-sacred elections and peaceful transfer of power and still have a government which isn't acting in service of its electorate. Sure, you can pick red corporate stooge or blue corporate stooge, but the Overton window is still a narrow slit that represents no real threat to the rich, and factionalism and winner-take-all elections sabotage any actual forward motion.

Meanwhile, the single-party state, unencumbered by having to tear itself apart in battles for the throne every four years, can focus on consensus and actual needs. Good governance can come from a sense of civic duty, or even a smartly weaponized corruption (if everyone thrives, my cut of graft grows with it!)