I’m in favour of speed cameras and the average speed cameras look like a good way enforcing speed limits on motorways. But saying they’re there to help cut CO2 emissions is just part of the current ‘carbonphobia’ hysteria.
Too many people drive too fast on the roads and excessive speed is a major cause of accidents. The faster you go, the longer it takes to stop and the harder you hit something if you fail to stop. (Clean driving licence for 37 years since I passed text at 17, ex HGV driver and reformed petrolhead*)
*now a dieselhead!