I suggest you start contributing to the zh-tw localisation on http://translatewiki.net instead of ordering others to fix alleged issues. There is a fall back chain which substitutes non-localised messages. Whenever the message is localised, it will be used instead of the message from the fallback.

There are plenty of possibilities to talk to the currently active zh translators.

Closed as WONTFIX.

Wouldn't it be an option, to include substitutions like these (likely better the entire automated conversion between zh varians) as a postprocessing after fallback from one zh to the other?
The outcome may be imperfect, but can assumed to be better than what we have now.

I sent a patch for these to translatewiki.net.

In the longterm I will just run my favorite tests at home, and submit patches.

Of course hopefully I won't catch anything, as nobody will put Simplified Chinese into zh-hant etc.

How they will manage not to do that is up to them...