I understand Youtube being the standart option for the "Video Overview" you can link to your profile. It's probably the most used in general but when it comes to Design and Motion Graphics / Animation professionals as myself, I think most will agree that a Vimeo profile is the standart and not Youtube. It's a bit frustrating not being able to link a vimeo showreel / demo reel link.
I see even Upwork has a Vimeo profile so why not? =)