Complex designs always present organizational challenges. The risks are indeed great. To my knowledge, these problems have never been discounted by aerospace advocates. Rather, they are seen as challenges to be overcome. Because the consensus has always supported the space program.
People seem to believe that it's worth the effort.
As a conservationist, I cannot speak for all the scientists on Earth. I am not familiar with every experiment that has ever been performed in space. But I can say that the space program has had a profound effect on the environmental movement. Before humans ventured into space, I think we as a species were fairly nonchalant about the way in which we treated our planet. At that time, we were literally choking on polluted air and sick from polluted water, and didn't know what to do.