There have been far worse such incidents, with dozens of fatalities in some cases, and the involvement of hundreds of cars. While statistically motorways are the safest type of roads (largely due to the ban on walking, cycling, and other forms of non-motorised traffic, as well as slower motorised traffic), pile-ups are the main factor pushing up the averages, unfortunately.
Another prominent crash pattern is that of the motorway pile-up. One person died in this one:
http://www.standard.co.uk/news/uk/a40-crash-witnesses-tell-of-horror-after-deadly-20car-pileup-in-thick-fog-a3428931.html
There have been far worse such incidents, with dozens of fatalities in some cases, and the involvement of hundreds of cars. While statistically motorways are the safest type of roads (largely due to the ban on walking, cycling, and other forms of non-motorised traffic, as well as slower motorised traffic), pile-ups are the main factor pushing up the averages, unfortunately.