Even new diesel trucks from Japan do this in places like the Caribbean. Maybe the standards are lower but I haven't seen a similar problem with new gas cars.
The US has way stricter new car auto emission standards than pretty much anywhere else, and I think lots of countries don't require DPFs at all, good point.
If the US standards get much stricter there will have to be PM filters on gasoline cars too.
If the US standards get much stricter there will have to be PM filters on gasoline cars too.