A much more credible threat are humans that get other humans excited, and take damaging action. Yudkowsky said that an international coalition banning AI development, and enforcing it on countries that do not comply (regardless of whether they were part of the agreement) was among the only options left for humanity to save itself. He clarified this meant a willingness to engage in a hot war with a nuclear power to ensure enforcement. I find this sort of thinking a far bigger threat than continuing development on large language models.
To more directly answer your question, I find the following scenarios equally, or more, plausible to Yudkowsky's sound viruses or whatever. 1/ we are no closer to understanding real intelligence as we were 50 years ago, and we won't create an AGI without fundamental breakthroughs, therefore any action taken now on current technology is a waste of time and potential economic value; 2/ we can build something with human-like intelligence, but additional intelligence gains are constrained by the physical world (e.g., like needing to run physical experiments), and therefore the rapid gain of something like "super-intelligence" is not possible, even if human-level intelligence is. 3/ We jointly develop tech to augment our own intelligence with AI systems, so we'll have the same super-human intelligence as autonomous AI systems. 4/ If there are advanced AGIs, there will be a large diversity of them and will at the least compete with and constrain one another.
But, again, these are wild speculations just like the others, and I think the real message is: no one knows anything, and we shouldn't be taking all these voices seriously just because they have some clout in some AI-relevant field, because what's being discussed is far outside the realm of real-life AI systems.
5) There are advanced AGIs, and they will compete with each other and trample us in the process.
6) There are advanced AGIs, and they will cooperate with each other and we are at their mercy.
It seems like you are putting a lot of weight on advanced AGI being either impossible or far enough off that it's not worth thinking about. If that's the case, then yes we should calm down. But if you're wrong...
I don't think that the fact that no one knows anything is comforting. I think it's a sign that we need to be thinking really hard about what's coming up and try to avert the bad scenarios. To do otherwise is to fall prey to the "Safe uncertainty" fallacy.