[WoodenChair]

> I feel like I could just go through the docs for for java / kotlin collections lib and cracking the code interview, and get a good understanding of DS / algos. What would this offer beyond that?

Reading the Java standard library documentation will teach you what pre-made data structures are available to you, but will not teach you how they work under the covers, or why they work. Reading Cracking the Coding interview will help you use data structures and algorithms specifically in the context of applying for jobs. If you want a deeper understanding you should do a course/tutorial/book that is more focused on the fundamental problem solving techniques like the linked Berkeley course.

In the book realm, I recommend Grokking Algorithms for a gentle introduction, or Algorithms by Sedgewick and Wayne for a deeper understanding. My own book, Classic Computer Science Problems in Java, is a gateway to the wider world of computer science. Yet, for sure this deeper understanding is not necessary for the majority of day-to-day dev work. However, if you have a curiosity, want to work on more fundamental problems, or be sure that you are always doing things the most efficient way possible, it is necessary.