The author is saying more that it's not just about how critical your responsibilities are to the company and how much you're given, it's about how much you enjo

The author is saying more that it's not just about how critical your responsibilities are to the company and how much you're given, it's about how much you enjoy said responsibilities as well. As an example, if you were to spend your days learning COBOL to chase the cash and work on legacy systems, you are probably having less fun than someone learning Python or Ruby or any number of more modern languages to work in a modern environment for what may be a lesser salary short term than that COBOL dev but can still give you a comfortable lifestyle in the long term as you become more senior.