Crossing the street in the morning is an exercise of how long can you hold your breath.
https://www.eea.europa.eu/data-and-maps/indicators/greenhous... [see fig 4 about targets for 2020 and actual changes in emissions for 2017 and 2018]
I think the average age of a registered vehicle here is around 10 years; it's not uncommon at all to see >20yo cars in local traffic and parking lots.
Taxes are higher depending on emissions, but it's rarely enough to offset the purchase price. For example, if you buy a stinky 90s car that emits 200gCO2/100km, tax would be around 300 eur/year today. A new car that emits 120g/100km is going to be somewhere around 150 eur.
Personally I prefer used imported cars, as well haha. It's just, if it passes technical inspection and emission tests, why not? An 8 year old VW or Toyota with all the options that's been well kept for 7000 Euros seems better to me than a 16,000 Euro new base model.
For getting around a city, public transport is good enough, though.
Another problem is just the number of cars - many cities have more cars than they can handle. Hopefully more cities will ban diesel cars or all cars in some parts...
Things are changing, slowly.