Also high IFR viruses usually have high symptoms. Much easier to contain a disease when you can tell people are sick. People feeling sick will also travel and spread less. What made covid so widespread is that it was so mild to so many people. So there is a kind of bell curve of deadliness vs infectiousness. So not really convinced by those argument of what if covid was so much deadlier. You would need a virus with zero symptom while you are infectious, and then that kills you, like an airborne HIV. Anything is possible but with ifs...
You understand that with globalization, this makes no sense, right? It will return, again and again. Economic impact of always going into lockdown will be insane. Another reason for western companies to become less dependent on China in the long term, massive reduction in productivity in the short term.