That video is of a rubbish dump, and it's talking about the amount of trash produced by Bangkok. And as Bangkok has about 10 million people, large amounts of trash are expected.
With some quick searching, I found estimates that the US per capita generates between 2 and 7 kg of waste per day per person. Thailand's number is less than 2kg.
I think the special challenge of a city like Bangkok is how rapidly it grew. But as evidenced by improvements in public transport over the last decade, I wouldn't be surprised if waste management had also improved. So perhaps it was much dirtier in the past.
And let's not forget tourism. 22 million people visit Bangkok per year, compared to 14 million for NYC. That's a lot of extra garbage that probably is not counted in the per capita figured.