html metadata - once in a <title> tag, once <meta name=title>, another in a <meta property=og:title>, another in a <meta name="twitter:title">. Probably some duplication for compatibility and different platforms.
2 times in <link rel=alternate> tags, for alternate versions of the site.
Actual displayed title below the video.
Suggested playlist mix - twice, one is the html tag 'title' and the other is the tag content.
Once for a title over the top of the video if the player is embedded in an iframe.
Once in a minified blob of javascript.
Basically all of these are ok use cases for duplicating data in the HTML. It's not excessive at all and I would have actually expected much more.
I don't know why the existence of metadata is a shock to the author.