I don’t know if this qualifies as a bug or “just” as a quirky implementation:
I try to split multiple audio files into mono. This works as expected, unless I try to specify a specific channel which I want to get extracted from all files (without having to delete the unnecessary second channel manually): In this scenario, the option for “Extract a Single Channel” is blocked. All selected files come from the same source (Logic … don’t ask …) and share the same length and format.
If this is the intended behaviour, then please change it for the better. 