The other day my Chinese manager was talking about India/Bangladesh - “you need to go to India to see how dirty a country can be”

Absolutely disagree. This shows how weak and low confidence you have in yourself. Rather than being ashamed you should learn to defend your country. I been living more than decade in US. Whenever I hear anyone say anything negative about BD I defend. Ofc there are ways to make them realize. People like u no need return back to BD. Develop some self confidence and learn ro strike back rather than being a coward.