On Thursday, 12 May 2016 at 20:15:45 UTC, Walter Bright wrote:
7. Autodecode cannot be used with unicode path/filenames, because it is legal (at least on Linux) to have invalid UTF-8 as filenames. It turns out in the wild that pure Unicode is not universal - there's lots of dirty Unicode that should remain unmolested, and autocode does not play with that.
This just means that filenames mustn't be represented as strings; it's unrelated to auto decoding.