The important thing about particulates is the 'particle number - PN' rather than the particle mass - PM.
Old engines spewed out a lot of stuff (bigger particles) that you could see. Modern diesels have a lot lower particle mass but the particles are a lot smaller because of the improved combustion., These are the most concerning as they can get through your lungs into your blood stream...
A PN limit of 6 x 10^11 / m3 was introduced a few years ago. Diesel Particulate filters were fitted to all diesels since 2008/9 which brought the tailpipe numbers down about 100 times lower. If you look at most diesel exhausts these days you will see they are still shiny on the inside of the taipipe (i.e. very little soot is getting through the DPF)
Now, PN from petrol engines has the opposite trend. It has gone up because of direct injection. Direct injection engines limit is 10 times higher so they emit about 1000 times more tiny particles than a diesel with a DPF. As this is stuff you can't really see, they don't get the nasty press like diesels.
Because of this all petrol engines are going to have Gasoline Particulate Filters (GPF) fitted. However, as the petrol engine is much more sensitive to back pressure, the PN will still be higher than a diesel.
Next, NOx - All EU6 diesels have very good NOx control through use of SCR (adblue system) or LNT. As such, they are also no worse than a petrol.
I wish these journalists and government bodies would be honest and clear about the latest diesels. The industry has spent billions and billions of pounds developing this stuff for politicians and other people that don't know one end of an engine from another saying we should ban diesel, its absolutely crazy.
I can understand limiting combustion engine use in cities, that is just common sense in general but its just going too far really to say ban diesels.
Just think how the price of petrol would go up if that happened!! Or the price of a unit of electricity!