It’s definitely self-promotion, but I don’t see why this is a bad thing. He’s clearly spent a large portion of his life developing a programming and computing e

It’s definitely self-promotion, but I don’t see why this is a bad thing. He’s clearly spent a large portion of his life developing a programming and computing environment to handle mathematics (and other things). What is he supposed to do? Write a blog post about something he's interested in, without using the programming language he has intentionally developed to deal with the things he’s interested in?