> https://support.google.com/youtube/answer/171780?hl=en
The YouTube API Terms of Service and Developer Policies apply to all access and use of the YouTube embedded player.
> https://developers.google.com/youtube/terms/developer-polici...
You and your API Clients must not, and must not encourage, enable, or require others to:
use YouTube API Services to create, offer, or act as a substitute for, or substantially similar service to, any YouTube Applications. API Clients must not mimic or replicate YouTube's core user experiences by recreating features or process flows unless they add significant independent value or functionality that improves users' interactions with YouTube. For example, an API Client must not recreate the browse experience from any YouTube Application without adding significant independent value to that flow.