You are confused as to how we utilize the PHAR archives. We don't unpack and place the individual files into respective folders, instead we include the archive (via phar stream wrapper) and use what is needed on page loads. So the .phar
will always be a PHAR, it will never be unpacked and placed into folders unless of course you are making edits to the core files. Here is a good read on how to utilize PHAR Archives:
As mentioned in the comments above, this is definitely an issue with the download manager. We are currently looking into this and should have a resolution sometime this week. For the time being, you can simply download each language pack individually (one at a time). I will update this thread when we have a fix in place.
Cheers.