I actually don’t like when technical blogging/writing is too casual, that’s distracting to me, the author isn’t my pal. It shouldn’t be excessively formal (as you’ve titled it) either, but neutral and matter-of-fact. For example, I enjoy Dijkstra’s writing style.

I think the biggest anti-pattern is not writing for who you are targeting, your intended audience.

I think your anti-patterns apply very well to the stereotypical SWE or HN reader, and if that is who you are targeting, you should absolutely follow these. But the biggest anti-pattern of all is following these anti-patterns while hoping to appeal to the untypical SWE or HN reader.

Friday will be the 20th anniversary of my first blog post, and I will continue to write sequels to my previous blog posts, and you can't stop me! ;-)