The Software Mansion folks designed it and we actually iterated on the designs on Figma, having discussions as humans, and exploring alternatives. They were lovely to work with.
I also worked on all of the copy myself, collecting feedback from core maintainers as I went. The new tagline was a suggestion from Theo which we iterated on. I did use LLMs as an assistant, but I did not ask it to generate the content.
Might as well use LLMs for the whole thing next time, since we will be accused of doing so anyway! :D
Shame then that despite all that, they landed on the same design used by every "I asked an LLM to make me a language and a website this weekend here's what it spit out" project. I mean, I'm not saying it looks bad or is a bad result. Just it's very similar to other things that have put in much less effort.
Ignore the haters, it looks very good.