I'm the lead author of the piece and I agree there's a lot more work to do on these issues. That's why we set up 80,000 Hours.

We address one of your questions in a later article: how to work out what you're good at https://80000hours.org/career-guide/personal-fit/ (And beyond this, you need to make predictions - I think the book superforecasters is good on what to do there)