Per https://hsivonen.fi/encoding-telemetry/, it looks like they run a special encoding detector on .jp sites, which is presumably designed specifically to choose between the various Japanese encodings (Shift-JIS, EUC-JP, etc).
I think your example of emergency services is a bit hyperbolic. This is a feature that is really not often used, whose omission is not fatal, which often requires several tries to get right, and which is increasingly less useful thanks to gradual changes on the Web. Much more widely-used features like FTP and Flash have been deprecated; people howl and yell every time, but yet things still seem to work.
I think your example of emergency services is a bit hyperbolic. This is a feature that is really not often used, whose omission is not fatal, which often requires several tries to get right, and which is increasingly less useful thanks to gradual changes on the Web. Much more widely-used features like FTP and Flash have been deprecated; people howl and yell every time, but yet things still seem to work.