I’m afraid to ask where in America is that common sentiment about Singapore. The only misconception I’ve ever heard about Singapore is being executed for possessing chewing gum.
Yeah, that does not surprise me. Americans are not always that great at global geography.
I'm not sure why that is. Of course the country is huge, and American culture is such a dominant force that it is not so hard to live your entire life and never learn much (anything?) about a relatively small city-state far away in Asia. If you've never met anyone from Singapore, this doesn't surprise me at all.
It still feels like something that the US should be better at as a nation, though.
I think it's less common now due to stuff like pictures of Marina Bay Sands going viral over the past several years, as well as movies like Crazy Rich Asians "educating" people that Singapore is a modern city. But around ~2010, not so much.
And I don't think it is just astroturfers, either. Given the above paragraph, I think it's understandable that many Chinese become quite defensive about the fact that they/their countrymen aren't, in fact, savages. I spent some time living in Asia, and even just from that (without any stronger roots like growing up there or having a culture based there), even I personally became quite frustrated and 'defensive' when having to constantly inform my American friends that yes, they do have electricity and running water in Singapore. I can imagine that someone actually from those places would be even more defensive.