Not a bug.
No, Phobos is *clearly* in the wrong here. There is a proper fix. http://dpldocs.info/this-week-in-d/Blog.Posted_2019_11_25.html#unicodeUse the correct WriteConsoleW api instead of the ancient ascii api. WriteConsoleW works without changing any settings. (on old versions of Windows, you may have to install fonts to display it, but new ones come with it all preinstalled).