The whole "languages" section sounds like it was written by somebody with no understanding of how dubbing is produced, who pays for it, and the issues that arise with the rights to these different versions of a film. Often it gets even more complicated with TV Shows. Convenience? Now you're getting completely unreasonable. If you can't filter by all metadata you're going to "steal"? Come on...
I'm guessing the point they were trying to get at was, you should be able to download and share subtitle files -- which are only useful to people who already have the movie -- without fear of prosecution.
"I have access to the audio in every language that has been produced."
Even the subtitle issue is complicated. Are these fan-made subtitles? Otherwise, again, you're entering a minefield and the chances of something like that ever happening within a unified interface — as requested — are slim.
Something like that would require a fundamental change to how films and especially TV Shows are distributed in other countries. Not to mention the technical issues that will occur due to certain countries getting a slightly modified (whether censored or extended or just modified) version of the original.
You're far more likely to get somewhere if what you're asking is at least somewhat reasonable.