Not sure you really answered the question, which I found to be a very interesting one. The OP starts with these two assumptions, which it sounds like you agree

Not sure you really answered the question, which I found to be a very interesting one. The OP starts with these two assumptions, which it sounds like you agree with: 1) SMI is likely to occur at some point in the future. 2) SMI is likely to pose a significant threat to humanity. Given those, it follows that we should be worried and plan for how to deal with SMI at some point in the future, ideally before it is developed. So the question is, what does the world need to look like before we worry/plan for it? And why isn't now a good time to start?