Long story short: to support YouTube tracking we need the "enablejsapi" parameter to be true (1) in the YT embed code URL, we also need a way to reference the iframe for example using the id attribute.
My suggestion is in the
get_the_post_video() function located in general.php add a filter on the embed code and preferably also on the source URL. Ideally I'd like to be able to choose my own attributes and source parameters entirely but I guess it would be acceptable to manipulate the entire HTML as well.
As of now we must hardcode changes in the source code to get the intended behaviour, of which are of course overwritten on update.