I think part of it is to answer the challenge. If we say nothing ever, it makes it appear we cannot answer the challenges with a sound response. Again, we have nothing to fear against science, science is on our side. God is the master of “science”. What passes for “science” today is a joke. It is not objective, it is dogmatic and cannot handle objectivity. I give you global warming. I give you in the 1970s, the coming global ice age. I give you eggs (good, bad, good again), I give you butter (good, bad, better than margarine good again). I give you the appendix and the coccyx. and a whole host of other organs ad structures once considered vestigial by the biggest and brightest minds of “science”.
I think part of it is to educate and strengthen the belief of our brothers and sisters in Christ, especially those that may have weaker faith and don’t know how to respond to the attacks of the evolutionists. Or anyone trying to undermine the faith of others. They don’t have to feel stupid or embarrassed if they have a reasonable answer that they can understand and explains it for them.