The answer I got yesterday from Tech Support:
Youtube has recently refreshed their webpage design, and it looks like the new design is not yet recognized by the Web Clipper.
I have opened a case to report this issue to our product team for investigation. At this time I’m not sure when the issue will be resolved.
As a workaround in the meantime, you can try clipping this page with a different clipping action, such as the 'bookmark' option.
I encourage you to continue updating the Evernote Web Clipper as new versions are released. You can find the latest updates and news about the Evernote Web Clipper on our product forum here: Evernote Web Clipper user Forum