You're not wrong, but one rarely needs to impress a person better than me to get a job. Hiring managers are rarely subject-matter experts.
That company will likely not have good developers, will be an engineering shit show, and worst of all you will have little opportunity to learn or gain good experience.
OP liked something well enough to write a post on it and shared it. I thought the writing was insightful and intriguing. Sure, the official docs contain the same information but I've read that tiny snippet and never retained that information. This way I'll be able to remember this for a longer time.
Also there's nothing wrong with writing a simple post in your blog. The internet isn't going to get full.
Over the last week I've seen two blog posts by the same person being recommended by Medium to me scoring programming languages in a laughable way to recommend their favourite niche languages.
That does way more damage to someone's hireability than a post about Python's print function.
Someone mentioned that it's a resume puff piece, but to me, it does more harm to the person that wrote it than good. It exposes his superficial level of understanding and lack of deep programming knowledge.
Would you hire him based on this? I wouldn't.
To end on a positive note, some advice to the author:
Programming is a field where you can't really hide your skill from people that are better than you. This means that "fake it till you make it" isn't a viable strategy. Embrace precision in your writing and avoid guesswork. If you're guessing about behavior, state so (or better, do research so that you don't have to guess). Ideally, you produce technical posts that go deep, have something to say (about the problem at hand or yourself) and are not mere regurgitations of surface-level knowledge. If you don't have something interesting to say, say nothing.