There's a big difference between understanding data structures and algorithms and being really good at solving algorithmic puzzles under time pressure. The form

There's a big difference between understanding data structures and algorithms and being really good at solving algorithmic puzzles under time pressure. The former is what you need to know to do your job well (and much of that knowledge is at your disposal with a quick google search) but the latter is a useless skill that doesn't help you with anything but passing a coding interview. If you want to be hired by FAANG, don't waste your time learning intricate algorithms, but simply practice to solve coding puzzles in record time on whiteboards. It's a totally different skill set.