Has our pollution problem improved?

No. The reason it has not improved and the reason it will not improve in the forseeable future is because the US government plans to allow companies to continue polluting if they pay for it. The way it looks right now, it will be less expensive for a company to pay for exceeding it's allowed level of polution than the cost of reducing the pollution itself. Even if the government were to pass laws requiring all companies to reduce energy consumption and pollution levels; how would they enforce the laws? Financial fines or even shutting companies down for violating emission standards would just cause lots of people to lose jobs. Voters who lose their jobs because of something their elected officials do to them tend to vote for "new" officials to replace the old one. Hopefully the price of a protective gas mask won't get too high for the average income earner to afford.