The air quality in Delhi was bad in the 1990s, got better, but now it’s the worst ever and many times worse than it is in Beijing.
The smog isn’t good for flights and it’s going to make for quite some mess in traffic of all sorts as the fog season comes in harder.
I minimize my time in Delhi because of how bad the air pollution is — more so at this time of the year. It’s not going to improve enough for me anytime soon.