Comment by newpavlov

In most cases locale is encoded in character itself, i.e. Latin "a" and Cyrillic "a" are two different characters, despite being visually indistinguishable in most cases.

The "language-sensitive" section of the special casing document [0] is extremely small and contains only the cases of stupid reuse of Latin I.

[0]: https://www.unicode.org/Public/UCD/latest/ucd/SpecialCasing....