I don't think "Less Wrong, Roko's Basilisk cultist" is a charitable characterization of Fernando: he explains the development of his current positions in https://borretti.me/article/the-education-of-a-doomer:

  If you follow me on Twitter, or read this blog, you have noticed that I went from being generally optimistic and excited about AI to being extremely concerned. And I thought, I should explain why I changed my mind. Each section of this post is about some aspect of AI where my views shifted. I begin each section by explaining my previous beliefs, and why I held them, and then explain why those beliefs changed.

I’m referring primarily to the commentariat rather than the author.