Far be it from me to insist, though, but if we indeed reimplemented all
the good parts of 'find', that would make the new function a suitable
replacement/improvement, at least on local hosts (instead of it just
being used as a fallback).
The basic problem here is this: the regexp or pattern to filter out
ignorables is specified as a Lisp string, which is in the internal
Emacs representation of characters. So to compare file names we
receive either from Find or from a C API, we need either to decode the
file names we receive (which in practice means they should be Lisp
strings), or encode the regexp and use its C string payload.