I hope you realize that you are asking about the hypothetical, because we Earth-bound humans have not made contact with aliens, let alone learn about their culture. So instead ask yourself why people here wear clothes. No referring to Adam and Eve.
Look at every culture on Earth. Even those who hardly wear anything at all as is the case with some Amazonian tribes and bush people of Africa. Elsewhere we all need clothes to stay warm but not in the hottest most humid places. Even in the jungle though, most will have some kind of cover over their private parts, if for no other reason that they are delicate and need protection from elements and critters.
Even nudists wear aprons when cooking food. Don't need hot bacon splatter where it will hurt the most.
There are no PEOPLE on other planets, as far as we know. Even if Life is proved to be there, it is not an easy jump to conclude that People there. Jumping to such a conclusion is like jumping over the Gulf of Mexico to Yucatan peninsula.
It isn't that simple.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.