PG&E lost $14 billion in 2018 and 2019 and had a relatively low profit margin in previous years.
In any case, this has little to do with the lack of available energy which you attribute to:
"demands put on neighboring states grids, which would have normally provided surge elasticity."
But why has California become dependent on energy imports from neighboring states?
Because it's producing less energy (ie, switching from nuclear to renewables) at the same time demand is rising.
And here's some real irony for you - much of that imported energy is from coal and gas (about 75% for LA).
This is similar to what's happening in Germany. They made a big deal about banning coal and nukes, but then increased their imports of coal-fired energy from other countries.
Anyway, if you click through the links in the story, it's all pretty clear. California's green energy policies are reducing its ability to produce enough power, hence the brown and black outs.
It's really appalling governance for a modern state like California, but it's not isolated to energy. The state is not well governed overall and explains the accelerating net-emigration to other states.