The Bolt shouldn't be given a pass just because it's FWD and very small... therefore needing to put all that stuff in the front. If the price point is essentially the same, the range is essentially the same (Tesla has the edge), the question should be why Chevy felt they needed to build a subcompact Frankencar.
It suggests several things to me... One, (perhaps most importantly) they need to make it that small and light to get the advertised range. They are lagging in the technology department.
Two, they're still thinking linearly in terms of 'engine/transmission in the front, passengers in the middle, gear in the back'. They didn't look at all the necessary drivetrain parts and say "let's think outside of the box and see how we can reorient everything based on radically different space constraints."
Three, they probably haven't given crash testing results as high a priority as Tesla. The space up front (empty for the most part) helps make the car safe. Chevy looks to have the same engine submarining problem as with ICE models.
Chevy, and even BMW, haven't really taken the EV transition seriously. They can't build the numbers to make a dent in the market. They haven't pondered the recharging infrastructure requirements. And clearly they haven't recognized that buyers might actually care what the car looks like.
So what is Mary Barra thinking? Probably something along the lines of "Oh crap, I guess we actually might have to build something that isn't a retrofit ICE". Or, "I wonder whether I'd enjoy early retirement?"