We seem to agree that clothing does not make it’s own meaning. I think it has to come from the surrounding culture. You seem to say, that meaning can be put into it intentionally. That is our disagreement.
Rav Miller’s essay does not support your theory. It points to specific clothing being silly. (The mets cap.) People could attach serious thinking to their clothing. But they do not. You have even attempted to make that argument with the yeshivishe levush.
In the old world, there was a lot of importance attached to many trivial matters. Therefore, everything in life was attached. Changing your outfit could lead one to being excommunicated. It is not like that today. And it is a poor argument that we are inferior because of it.
The fact that it is required points to how shallow it is. If it really meant something, than the value of it could be taught. Then, people would want to wear it. Only because it is meaningless, it has to be “enforced”. Clearly, meaning still has not been put into it. If your friends want to make meaning out of it, they can go right ahead. But who is to stop them from attaching some awful meaning to it?