IMO the most jarring issue that comes from Han unification without proper language setting isn't with the glyph variants, since you actually encounter these var

IMO the most jarring issue that comes from Han unification without proper language setting isn't with the glyph variants, since you actually encounter these variants and more in everyday life (albeit more rarely than your national standard ones). The more jarring issue is when your software selects a font meant for the wrong language, and the font for the correct language as a fallback. Then you may encounter serious style issues where your text is pockmarked by glyphs for another language; you have a similar phenomenon with European language using Latin alphabet with unconventional accents. But note that it takes way more effort to ask a CJK foundry to cover all codepoints for all languages than to ask a Latin font designer to cover all languages, so you would be hard pressed to find fonts that actually do that. Without Han unification, this wouldn't really be a problem, but Han unification is to a large extent the same philosophy pursued with unification of Latin scripts (and other scripts)