I agree that it's mostly safe, but green, or clean? And the public transportation is a mixed bag, my daily commute to the office used to be 1h each way (around 6 miles distance). Cost of living is ridiculously high compared to the rest of Poland, software engineers, businessmen and celebrities are probably the only ones who really can afford it.
But the main reason I'm leaving is because people here are assholes. As a capital city of Poland Warsaw attracts the worst kind of scum, politicians, wannabe celebrities, con men, corporate drones, gold diggers, etc.
If I could have one wish it would be for Putin to nuke Warsaw.