Most Hijabis are modest. Inc Somali hijabis.I believe most girls only wear hijab because of family/community pressure and not because they are spiritually ready.
There's no other reason to explain why there are so many loose hijabies and I don't mean sexually.
Yes you may see a few ratchet and immodest Hijabis but the vast majority aren't like this, but the loudest voices are heard the most.