"economics still pays little to no attention to externalities"

Absolutely. The world is complicated in ways markets don’t/can't take into account. All the talk is about profits, but too often ignored are the costs – both financial and otherwise. The environment being possibly the worst example.

For instance, nuclear power. As a person of science, I'm often challenged by other scientists and capitalists that I should support nuclear energy because it's clean and less expensive than green technologies.

Sure, except.

For instance, don’t tell me it’s cheaper until you factor in waste disposal. Price it to account for that.

Also, don’t tell me it’s cheaper and safe until you've accounted for the possibility of disaster. They act as if things like Chernobyl and Fukushima never happened or will never happen again. Yes, solar is expensive, but it isn't going to blow up and create enormous costs and environmental damage.

No talk about costs and profits until all the known externalities are taken into account (plus some more for the unforeseen ones that will inevitably appear).