Some people find it smells bad
I'm a Westerner and I really like durian. Durian is the breakfast of champions. I'm half Taiwanese but I don't think it matters and most young Taiwanese don't like it either. It’s more of a Southeast Asian thing.
As for why most Westerners don't like it, it's because the smell is very strong and some people find it unpleasant.
Bad choice of imports
I'm pretty sure I don't have a drop of Eastern blood coursing through my veins. I am more than happy to eat and enjoy durian and have done so many times during my travels. I've never had it in the West. I suspect that the smell, combined with the fact that the fruit itself is more susceptible to damage than you might think at first glance, makes it a poor choice to import compared to lychees, and it doesn't grow naturally here.
Stinky cheese
My wife loves soft, smelly cheeses like Limburger and Muenster. I'm not a fan. To me, they smell like garbage...or durian. My wife was very happy with the durian. She said she could understand the call. Every Westerner I asked who liked durian also liked stinky cheese. They have similar texture and smell. My theory is that it's probably a mix of the structure of their noses and mouths and the knowledge of how to eat these foods properly. Tasting is more important than smell. However, my research is entirely non-scientific and anecdotal.
on first try
Durian, like many things, is an acquired taste. But Westerners can and do eat it. When I first tried it, I didn't like it. But when I first tried Guinness, bitters, and many other things, I didn't like them. By constantly trying these things, they have now become some of my favorites
Not widespread
It's not widely available, so many people don't have it. In my local Asian supermarket, they sell imported durians. Available both canned and fresh (flew in), I eat them when they're in season.
no biological reason
There is no biological reason or international law that can stop them. They didn't eat it or taste it when they were kids. The same goes for mainland Chinese, until they got used to it and are now its biggest fans. Many non-Southeast Asians cannot tolerate the fruit, but since the world is dominated by Anglo-Westerners, they are concerned.
Pinch your nose and taste the durian
The durian's sweetness isn't the issue, it's the flavor. Let Westerners pinch their noses and taste durian, and everyone will find it sweet. The sugar in the fruit triggers the taste buds to recognize the "sweet" taste.
However, tasters must cover their noses as most Westerners find the smell offensive and regard it as "non-food". When asked to identify smells, they came up with things like "sour gym socks," "rotten onions or peaches," or "all of the above."
Sweet and creamy
The overall taste of durian is sweet and creamy. Some varieties have an extra bitter taste. Others were said to be drunk. When people eat durians that naturally fall from the trees for an hour or two, they will have a numb taste, just like eating Sichuan peppercorns.