Comment by dwheeler

Not to the same degree, though, and the arguments for status quo are especially weak. There are reasonable arguments pro and con case-insensitive filenames. Character encoding issues are dwindling, since most systems just use utf-8 for filename encoding (as there is no mechanism for indicating the encoding of each specific filename), and using utf-8 consistently in filenames supports filenames in arbitrary languages.

Control characters in filenames have no obviously valuable use case, they appear to be allowed only because "it's always been allowed". That is not a strong argument for them. Some systems do not allow them, with no obvious ill effects.