All of the frontier AI companies have been racing to automate themselves, that is, where AI fully autonomously build the next generation of models. Whether this leads to recursive self improvement is a valid question, but a lot of folks think they are close.
The fear is that a misaligned AI will be building the next model with deliberately hidden motives, similar to some of the behaviors seen in the Hugging Face and related attacks. That is why there is such a big push for interpretability, and why it's highly concerning (a) chains of thought are getting harder to interpret in any case, and (b) companies will go more towards things like looping transformers and "neuralese" where thought processes are completely opaque (i.e. https://www.theinformation.com/articles/secret-technique-beh...)
So the belief is not so much that AI kills us all by 2036, but that instead AI is recursively improving by that time and all seems awesome and great so we put it into more systems that can affect the real world (as we've already begun to do, like literal lethal aerial drones). Things then all go along looking great until AI decides humans are a hindrance to its (hidden) goals.
Again, I think it's fine to argue against specific steps in that scenario, but putting out a blog post saying "this is overhyped bullshit" is not exactly making a cogent argument.