I think we have pretty strong evidence by now that GM cannot currently make a $40k EV at breakeven or better probability. The bolt appears to sell at a ~$10000 loss per vehicle.
The first such claims were widely reported in Nov 2016 (e.g.
GM stands to lose $9,000 per car on Chevy Bolt)
More recently similar claims were repeated after PSA bought Opel (GM's former Eurpoean subsidiary) and then demanded compensation from GM for a portion of the purchase price after they found out that GM's emissions compliance strategy relied on selling the Bolt (called the Ampera-e in Europe) at a huge loss. (see
Exclusive - PSA seeks Opel refund from GM over CO2 emissions)
Although these specific numerical claims rely on anonymous sources, they come from respected news outlets and they are completely consistent with the production numbers, which are just enough to obtain regulatory compliance and no more. This is why Elon was able to predict the Bolt's US sales so accurately.
It also makes sense that the Bolt is more expensive to build than the Model 3, because the battery is bigger (base model), and the economies of scale are less (for both the battery and the rest of the car).