Yes, this appears to be across all YouTube embeds. If it really bugs you, like it does me, I'd suggest showing the thumbnail and then swapping it out on click to the video with autoplay on. I wrote about doing this using jQuery years ago here: start/play embedded (iframe) youtube-video on click of an image
Your thumbnail is avaialble at: http://img.youtube.com/vi/YOURVIDEOID/maxresdefault.jpg
I was tidying up an AngularJS YouTube directive when they made this switch and I spent half an hour trying to figure out what I'd done to create that black border around the thumbnail until I looked around the internet at other embedded videos and noticed that it was YouTube system wide. Heh.
No idea why YouTube decided to do this, it looks horrible.
Try setting the iframe size using css, initially inline like this:
<iframe style="height: 1080px; width: 1980px" src="" frameborder="0" allowfullscreen></iframe>
If this works, neaten it up by giving the iframe an id and then add the dimensions as a rule to the external css file.