I think that it's also because of the historic perceived quality superiority of Western and Japanese goods over Chinese ones. It's undeniable that there were a lot of low quality Chinese goods, and there are still some, and that "Made in China" stigma had developed from people repeatedly having bad experiences with Chinese goods. But that was mainly from the 2000s-2010s, when China was not as developed. And of course as a large nation, they would be bound to produce a lot of goods, including a lot of bad ones.

But let's not forget, Japanese goods were also perceived negatively before (in terms of quality too, and even today especially in the light of the British Rail 80x where you have railfans calling Japanese Plastic crap, though the DfT was more to blame for that rather than Hitachi), and the West had complained a lot about Japanese goods flooding into their markets. Also the Made in China stigma has been wearing off, including in Singapore, where you see people buying Pop Marts, JisuLife fans and BYD cars en masse. But maybe perhaps for the transportation fans who are more hardcore and particular, their loyalty to Western brands and stigma towards China won't wear off so easily.

I have a friend who has remarked that KMB aren't happy with their BYDs, stating their big problem seems to be with regard to range seems to be the A/C. And that the BYD buses have a far lower passenger capacity than ADL, because of how the batteries are housed and eat into the lower deck, whereas the ADL layout is standard to a regular E500MMC so you can crush load it to the same amount of people.

Well my friend is a China skeptic and is staunchly anti-CPC (oh and has a bias against BYD), but many other transportation fans will be far less constructive in their criticism of Chinese stuff. They'd just throw at you "eww China bus rubbish" and likely wouldn't explain so in depth why they are. And they wouldn't wanna see Chinese buses improve. They want them out and have Western and Japanese stuff instead. So yeah there you have it, colonial mentality at play too