Like every other aspect of school discipline, a mandatory uniform is by its very nature inherently an exercise in reducing interruptions to the classroom with the express intent to optimize learning on the basis that an educated population of high-school graduates increases societal liberty as the desired end result.
But I'm honestly curious: since you're no fan of any school that isn't modeled on A S Neill's Summerhill, which would you consider to be /worse/ or perhaps least evil: mandatory uniforms in a public school, or a public school that teaches reverence for uniforms but doesn't require it for their students?