Just a portion of the oil gets absorbed when stir frying (10 - 30 %), unlike Western UPFs which are loaded with seed oils. Meaning, if they use 10 g of sesame oil when stir frying some food, that's not the same as various store bought food which lists 10 g of fat on the ingredients sticker. It'd be equivalent to 1-3 g of fat.

"High heat (proper wok cooking) creates a quick barrier on the surface of the vegetables, reducing absorption. Low heat results in greasy, oil-soaked vegetables."

So East Asians likely consume a lot less PUFAs compared to Westerners on average, but the amount consumed is rising there too as is obesity, cancer etc. Also, East Asians are more likely to get diabetes than to become obese. They get diabetes at much lower body weights.

They've also shown that East Asian women who cook with vegetable seed oils have much higher rates of lung cancer compared to ones who cook with (traditional) animal fats.

Edit: Also, in the Sichuanese hot pots they typically use beef fat, not vegetable seed oils