Well, when I say that they retrofitted unicode elegantly, I'm ofcourse comparing it to how unicode was retrofitted into PHP. Elegant is in the eye of the beholder I suppose.
The same goes for maintainability. Upgrading the codebase was a sizeable effort for sure, but in my view it was less than it would have been had it been developed on another platform.
Unicode was retrofitted into PHP and then the entire effort was abandoned, so yes, i think anything would be more elegant.
PHP currently supports unicode in the same way as lua or C - every string is a binary string. If you want correct UTF-8 behaviour in string functions then instead of using libc or string_ functions, you must pass the character set as an additional parameter to specialised mb_ string functions instead.
The same goes for maintainability. Upgrading the codebase was a sizeable effort for sure, but in my view it was less than it would have been had it been developed on another platform.