So was Afghanistan. But a short duration of military dominance and writing words in paper can’t change the culture of the people. Colonization, as with Hong Kong, or a generation of top-down rule over a small population, as with Taiwan and Singapore, can. Again, read Yew. He was deliberate and methodical about all this, and has written and spoken widely about what he did to transform Singapore.
Great comments, though one small nitpick: For Chinese names, the surname goes first, so for "Lee Kuan Yew", his last name is "Lee", not "Yew". He's often abbreviated as "LKY" for locals though.
Interestingly, LKY was known as "Harry Lee" until he became active in politics, upon which he went by "Lee Kuan Yew" to apparently help endear himself to the local Chinese population. He took Mandarin lessons well into his old age as it wasn't the language he spoke at home. I think most of his counterparts overseas knew him as "Harry" (Thatcher, Kissinger, etc) and even his wife called him "Harry" per biographical accounts.
Lee was undoubtedly a product of the British system - an English-educated ethnically Chinese man, straddling both sides in order to navigate those early years.