I wouldn't be so harsh. The author of the blog post is also the author of the paper. If I had to guess, the author decided (or was advised) that writing a blog

I wouldn't be so harsh. The author of the blog post is also the author of the paper. If I had to guess, the author decided (or was advised) that writing a blog post about the paper would increase its visibility (which turned out to be true, considering it's on HN). So they wrote a blog post summarizing the paper. But because they are really deep in the weeds with the technical content of the paper, might not have done a great job at making it more accessible to a wider audience. Doing that well takes some skill, and is not usually something graduate students get much, if any, training on. (Edit: on reading the blog post, I do have to agree that the presentation is pretty abstruse to the point that the paper is a better source. And yes, I am a "Phd level AI researcher").