Thank you, my thought here was to make the registration as quick and easy as possible - no email or confirmation is required.
I figured that someone would have to be somewhat invested in order to want to make submissions anyway - it takes longer to get the video URL and go through the submission form than to register.
An OAuth2/"login with your YouTube account" might streamline this for you, and facilitate sharing of collections already created on YouTube through their Data API.
If I (as a user) am sharing a video link from YouTube, in many (most?) cases I will already be logged in to YouTube, and reusing that credential would be easier for me than creating a new account registration on the third party site.
Edit: There's more: once you (as the service) have a YouTube account connected, you can offer a variety of additional services related to the YouTube Data API that a local account registration does not.
I figured that someone would have to be somewhat invested in order to want to make submissions anyway - it takes longer to get the video URL and go through the submission form than to register.