Loads of sports include wearing a particular "look". Beach volleyball, tennis, gymnastics, dressage, cricket, whatever. At least with cheer the lycra serve a purpose - easier to catch a falling body if it's shape isn't obscured by baggy clothes.
You can be any size any weight any appearance and be a genuinely valued and important part of a team. So long as you're strong, fit, and skilled you're face really doesn't have to fit.
Few traditionally mens sports are questioned in the way traditionally female sports are - its absurd that wonen and girls shoukd have to doubt if theirs is a "proper sport" rather than a way to titillate men.
It's competitive, it needs strength and fitness. Theres huge level of physical skill in competitive cheer.
It's no longer about cheering on the menz nor light entertainment: Dallas cowboys are a dance group and that old high school Mean Girls trope is really out of date bollocks.