It's interesting his choice is around what programming language you choose, as I kinda assume everyone I work with will be a solid programmer just as a baseline

It's interesting his choice is around what programming language you choose, as I kinda assume everyone I work with will be a solid programmer just as a baseline requirement. How well you can slot your code into complex systems and how to design those systems is usually what is difficult. We have way better resources for learning but also much higher expectations. You need to be able to write good code without much thought so that you can maintain a higher level of context while programming. Sometimes you get to write just a nice little isolated bit of code, but usually there are a lot of moving pieces. (no matter how functional and immutable we try to make it.)