The trend has already started. E.g. in Germany, some cities prohibit older Diesel engines within city limits.
This has lead especially commuters of low-wage jobs quickly being forced to buy a new, more environmentally-friendly car (and their Diesel car just lost a lot of value in the market), so they have no option other than switch to gasoline engines - which are usually OLDER cars than they used to be with WORSE pollution statistics.
Buying a new car is not affordable to them. Public transportation is a lot better than in the US, but still will not solve the issue completely, and where it is a viable alternative, it's expensive both in time consumption and in money spent.
With a new law that was meant to lower pollution (and the jury is still out on if the goal was achieved, as during the corona crisis, pollution sank overall), we've created worse conditions for the underclass and lower middle class.
This is how you destroy support for ecological policymaking. If you want a better world for yourself and your children, you cannot achieve it by making it worse for others and the present.