It may not be so infuriating when you consider how important names are to Japanese people. Breaking your name is unacceptable and breaking it because of a technical convenience chosen during development would be deeply offensive on top of being unacceptable.

Until Unicode stops breaking people's names, it will continue to be the one standard for Japanese systems on and offline. Even when(if?) it stops breaking Japanese names, it will take a very, very long time to roll over existing systems and that's precluding unforeseen problems during the conversion.

We should stop before we take the "not following standard" = "broken" ideology. Especially when we consider whom the standard serves best.

Edit: By "it will continue to be the one standard for Japanese" in the 2nd paragraph, I meant ShiftJIS not Unicode. That looked a bit unclear.