This is misleading, because it assumes that i/I naturally represent one vowel, which is just not the case. i/I represents one vowel in _English_, when written with a latin script. ̶I̶n̶ ̶f̶a̶c̶t̶ ̶e̶v̶e̶n̶ ̶t̶h̶i̶s̶ ̶i̶s̶n̶'̶t̶ ̶c̶o̶r̶r̶e̶c̶t̶,̶ ̶i̶/̶I̶ ̶r̶e̶p̶r̶e̶s̶e̶n̶t̶s̶ ̶o̶n̶e̶ ̶p̶h̶o̶n̶e̶m̶e̶,̶ ̶n̶o̶t̶ ̶o̶n̶e̶ ̶v̶o̶w̶e̶l̶.̶ <see troad's comment for correction>

There is no reason to assume that the English representation is in general "correct", "standard", or even "first". The modern script for Turkish was adopted around the 1920's, so you could argue perhaps that most typewriters presented a standard that should have been followed. However, there was variation even between different typewriters, and I strongly suspect that typewriters weren't common in Turkey when the change was made.

> 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.

>This is misleading, because it assumes that i/I naturally represent one vowel, which is just not the case.

It does in literally any language using a latin alphabet other than Turkish.