I wanted to report that there seems to be an issue here today with the Youtube Importer/Player in Studio: https://community.instructure.com/en/kb/articles/660482-how-do-i-add-media-from-youtube-and-vimeo-in-my-studio-account
For me I have a spinning circle, just when I need to demo in a workshop! It was working ok last week. We are in the process of migrating to Canvas so something may have triggered this. Also I am not sure if we have Tier 1 support with Instructure to know how to report issues like this - I imagine our IT will raise for us in time (I have let them know)