I don’t think that’s the right way to think about it. It’s not like they were Latinizing Turkish with ASCII in mind. They wanted a one-to-one mapping between letters and sounds. The dot versus no dot marks where in your mouth or throat the vowel is formed. They didn’t have this concept that capital I automatically pairs with lowercase i. The dot was always part of the letter itself. The reform wasn’t trying to fit existing Western conventions, it was trying to map the Turkish sounds to symbols.

They switched from Arabic script to Latin script. They literally did latinize Turkish, but they ditched the convention of 1 to 1 correspondence between lowercase and uppercase letters that is invariant across all languages that use Latin script except for German script, Turkish script and its offspring Azerbaijani script.