Strongly smells of LLM-generated content with all those bulleted and numbered lists, and so on. I'm not one to automatically find the use of em-dashes to be an LLM "smell" — I use them all the time myself — but there are five of them in the post, adding to my suspicions.

And then looking at the rest of the site's articles seems to confirm it: the "OOP in Java vs FP in Clojure" article (linked at the bottom of the site) is just classic AI-generated "here are the parallels between these two topics" boilerplate.

B-trees are indeed cool, but I would prefer to read about them from someone who has actually written about them rather than farmed off the writing to a bot.