No. It’s a minimum fuel efficiency standard that petrol cars registered after 2006 were legally required to meet. So it is a very lax standard in reality, and only removes the worst vehicles from the roads.
That’s what I’m saying / the congestion area is only for post 2006 vehicles.
The area is for all vehicles, and most petrol vehicles registered before 2006 must pay to enter it.
This isn't a congestion area, it's a low emission area. Vehicles before 2006 probably don't meet the emission standards and thus have to pay the premium. Cars after 2007 probably do meet the standards and thus don't have to pay the premium.