Maroon/burgundy doesn't suit a lot of people, but it's reasonably sober as a colour. Maybe "scarlet" is being used in a special way here, but I picture hordes of girls dressed from head to toe in fire-engine red (a color that only really looks good on someone with vivid coloring who is ALSO wearing a lot of makeup, or at least scarlet lipstick...) and it makes me shudder!
Re: "dreggy uniform dress"