No, I don't think it's typical of an early Model S. An NCA curve is very similar to an NMC curve and both very different to LFP and the graph you've shown.Most current Tesla cars have an LFP battery now (as will more than 50% of the fleet going forward), but that isn't the relevant question for this REUTERS attack rag.
10 years ago, Model S used a NCA chemistry, and before silicon anode (which wasn't added to Panasonic 18650s until the Model S P90 was introduced).
So the discharge curve I presented is typical of the Model S cell which Tesla was shipping 10 years ago. Notice howI didn't even mention the additional complications for estimating total energy available in a multi-cell pack?
There are also plenty of test curves around for early Model S 18650's that show a similar sloping curve, such as these: Tesla Model S 18650 Cell Test Data