I don't believe in feasibility of any scenario like AGI foom.

First, I fail to see how anybody taking an outside view on AI research - which is a clear instance of class of sciences with extraordinary claims and very long history of failure to deliver in spite of unusually adequate funding - can think otherwise - to me it all seems like extreme case of insider bias to assign non-negligible probabilities to scenarios like that. Virtually none sciences with this characteristics delivered what they promised (even if they delivered something useful and vaguely related).

Even if AGI happens, it is extraordinarily unlikely it will be any kind of foom, again based on outside view argument that virtually none of disruptive technologies were ever foom-like.

Both extraordinarily unlikely events would have to occur before we would be exposed to risk of AGI-caused destruction of humanity, which even in this case is far from certain.