BMW I4 Battery Capacity Calculation

After driving a Polestar 2 for 4 years, I’m due to pick up a 2022 BMW I4 M50 and noticed when planning my long journey home, it suggested that I needed to charge way more than anticipated.

Noticed that ABRP reports the i4 E40 and M50 (which have the same size battery) as 73.8kWh, however the gross capacity of both models is 83.9kWh with a usable capacity of 80.7kWh to 81.3kWh (depending on the production year).

Not sure if I’m missing something here, or if the capacity needs to be updated?