The modern Korean attitude is to transliterate sounds nowadays. It’s—in a way—taking the extreme position of divorcing from 漢字.
Some traditionalists that have more conservative views insist that is more proper to acknowledge the underlying 漢字 and pronounce the words as such.
In my opinion, this kind of transliteration is a half-baked attempt to sound like the source language. The 한글 transliterations usually miss a few details of the actual pronunciation in of source language.
Japanese [toː.kjoː] versus Korean [to.kʰjo]
Mandarin [pei˨˩.t͡ɕiŋ˥] versus Korean [pe.i.d͡ʑiŋ]
Vietnamese [viɜt̚˧ˀ˨ʔ.naːm˧] versus Korean [pe.dʱɯ.nam]
This is not done in Chinese where a place like Osaka (大阪) is actually called [ta˥˩.pan˨˩˦] in Mandarin rather than a phonetic approximation.
ㄷ is never pronounced like ㅌ in the initial position or between vowels. Although it is slightly aspirated, it is not strongly aspirated like ㅌ. However, they are both t; English does not make a distinction between the different pronunciations of t so the same letter represents many different sounds including those represented by ㄷ and ㅌ.
Why is the first place that I learn in Korean (and approximately the fourth word altogether) a city in Japan? (I'm not trying to be snarky, I am simply curious what sparked the decision to choose this particular word in the acquisition of knowledge of the Korean language and, for some, potential survival in travel to the country, which to the best of my knowledge, is NOT where Tokyo is located!)