Comment by troad
> In fact even this isn't correct, i/I represents one phoneme, not one vowel.
Not quite. In English, 'i' and 'I' are two allographs of one grapheme, corresponding to many phonemes, based on context. (Using linguistic definitions here, not compsci ones.) The 'i's in 'kit' and 'kite' stand for different phonemes, for example.
> There is no reason to assume that the English representation is in general "correct", "standard", or even "first".
Correct, but the I/i allography is not exclusive to English. Every Latin script functions that way, other than Turkish and Turkish-derived scripts.
No one is saying Turkish cannot break from that convention - they can feel free to do anything they like - but the resulting issues are fairly predictable, and their adverse effects fall mainly on Turkish speakers in practice, not on the rest of us.
> but the resulting issues are fairly predictable, and their adverse effects fall mainly on Turkish speakers in practice, not on the rest of us.
I don't think it's fair to call it predictable. When this convention was chosen, the problem of "what is the uppercase letter to I" was always bound to the context of language. Now it suddenly isn't. Shikata ga nai. It wasn't even an explicit assumption that can be reflected upon, it was an implicit one, that just happened.