Precisely, the interest of this article is to show, supporting figures, that there is a significant correspondence between accidents and social class, what the usual analyzes try (very well!) To conceal by a construction of globalizing neutrality.
I do not deny this aspect of dissimulation (I am usually opposed to all these dissimulations) but at the same time it must be taken into account that society has changed and that the social classes most affected are also those who have increased their power to purchase to become car owners. In my time, as the old people say (sorry the old ones) the young people (and most of the time their parents too) could not afford to buy a car and moved by bicycle or by motorbike with a population much less important and therefore the involvement in accidents was less, proportionally, than today. Currently, this category, constantly increasing therefore, wants a car as soon as possible, new or used, because our society is like that. So it is understandable, that it is the most numerous categories which are also the most affected, especially if we add the consumption of strong alcohols, narcotics, smartphones and other accident-causing products which are not as developed in the wealthy classes.
Moreover, by reading your argument, it seems that you did not read the article in question well ...; thus, it is specified there that far from your example of two vehicles "filling up", the "working" classes mostly killed themselves, by an exit from the road not involving another vehicle ...
Indeed, I did not dissect, but only read this article quickly enough and some nuances may have escaped me. I only mentioned the job because it was considered that high-end cars were better equipped, stronger, more secure.
But at 160 or 180 km the difference is hardly noticeable.
To "kill themselves alone", it is also necessary to analyze (apart from any social class) the reasons for these exits from the road. Inexperience, speed, alcohol and other drugs, fatigue, medication, etc… and as this social class is the most numerous on the roads, mathematically it is also the most affected.