The fear is not of reopening. The fear is of reopening either too soon or without proper precautions in place. Just because the curve has started to flatten doesn't mean we are through the thick of it. If you open too soon you just create a new curve. As I type this, in the U.S. we see over 10,000 new cases per day. In the world, we see over 100,000 new cases per day. That is a lot of new cases. And we don't know enough about this virus to say how it will mutate, what 2nd wave we can expect, etc. We are essentially reopening our economy in total blindness-before we know the full effect of this virus and before there is any proven treatment, cure or vaccine. Of course we cannot stay closed forever. What is happening several different things, but the main point is that our society is saying basically "More people will get sick and die, but we have to accept that so our economy doesn't collapse past the point of recovery." It's morbid, but that is the gist of it.