You CAN have an unambiguous code -- zero subjectivity -- that eliminates BS like this. Simply write into the code that the ONLY thing that defines a uniform is the singlet and the pair of shorts worn on the outer layer. If team members differ in this criteria, then you have an infraction. If someone decides to wear a neon green sports bra, leaves a hair band on their wrist, wears a necklace, wears their gloves because it is cold (and those gloves happen to have a swoosh on them), then under this type of code, it is simply irrelevant, as it should be.
A standard uniform requires a simple flowchart. Are the team members wearing identical singlet/shorts (except for size, of course)? If yes, continue. If no, violation. Do any of the team members have garments that obscure the team uniform (jacket, shorts over team shorts, etc)? If no, done and good. If yes, violation. We don't need anything else.
"Yeah, it seems silly, but rules/laws must be written in very specific ways and then enforced closely, or not at all."
I agree that rules should be unambiguous, but that does not mean that rules should dictate meaningless details. A law can say that something irrelevant is just irrelevant.
Close enforcement for all laws? Speed limits are pretty well-defined, but do you really think we need a cop with a radar gun on every corner?
"no matter how insignificant they may seem to us." Your wording here suggests a lack of knowledge on our part, as if the high school league had a meaningful, but non-obvious, reason for their rules. That is totally incorrect.
The role of high school sports officials is to ensure safety and fair competition. The color of the stitches on your compression shorts has nothing to do with these goals. On this basis, I argue against you: HS sports officials have an ethical duty to a) ignore these rules and b) seek their removal from the code.