Yes the mileage on the EPA label includes charging losses. The EPA also specifies efficiency on kWhr/100mi.
View attachment 27886
The Pure has an 84kWhr pack so Lucid calculates the driving efficiency 420 miles of range divided by 84kWhr or 5.0 mi/kWhr
The EPA shows efficiency of 23kWhr/100mi or 4.35 mi/kWhr. The details showing the inclusion of level 2 charging losses are in the testing procedure, not on the label.