if theyve been doin that for a while, no wonder the board wanted them gone. eventually you cause more work than you put out.
He talks about how learning ML made him feel like a beginner again on his blog (which was a way for him attract talent willing to learn ML to OpenAI) https://blog.gregbrockman.com/its-time-to-become-an-ml-engin...
100 hours is equal to 2 full-time jobs and a half time. People believing that number should consider how they would live going to their second job after their day ends (second full-time job) and working on weekends as well (half-time one).
Under ideal conditions, someone might be doing it. But, people shouldn't be throwing around these numbers without any time-tracking evidence.