For sure, but I think even if you didn't consider those particular examples to be a part of the fundamentals, if you had a solid command of basic algorithms and

For sure, but I think even if you didn't consider those particular examples to be a part of the fundamentals, if you had a solid command of basic algorithms and data structures (e.g., including your basic trees, including B-trees) and some basic math, you could easily pick up LSMs and figure out how to exploit the S3 cost structure as needed. The point of the fundamentals as commonly construed is to allow you to quickly pick up novel concepts as needed as they're almost always a slight extension of the fundamentals.