throwaway2019G

Read the actual comment.

Generally very true. Ultimately it's just a game of leverage. If you're hyperspecialized and irreplaceable, you have essentially unlimited bargaining power against your current company. At the same time, if you're hyperspecialized and irreplaceable, you likely have less bargaining power on the general market because you've overspecialized.

Being irreplaceable. I worked on a team where our full-stack engineer put in nights and weekends consistently and received a $100 gift card for Christmas. Our data architect worked reasonable hours and received a 5 figure Christmas bonus because he was the only person in the company that truly understood how our vital algorithms worked (he wrote them).

Our full-stack engineer left soon after that.

That's because these guides are specifically designed to help someone pass an interview. What you're describing is the experience that one would get from taking an online data science course.