Can't agree more with AROTC-dad, the environment plays a part.
I'll just toss this out there for comparison.
My older so interviewed at the University of Washington, the flagship school in our state, he wore slacks and a collared shirt, no tie. After the interview they gave him a short tour of the offices and there were a number of current cadets in the office. There must have been an interview just before my son's appointment because as we walked around we overheard a group of cadets laughing and saying that at least this kid didn't show up in a JROTC uniform. While wearing that uniform may seem like a good idea, it may not be received by others as well as you might think.
Younger son spent a weekend at the ROTC battalion where he had scheduled his interview, he participated in morning PT and when finished the PMS had him come to his office for the interview. Son did his interview in shorts and a T-shirt.