Why are there not mnemonic-seed words in Turkish especially considering the increasing rate of bitcoin adoption in the country? How come bitcoin doesn't have Turkish words as wallet seeds especially considering the increasing rate of bitcoin adoption in the country ?
Because no one has stepped up to do the work or hire someone to do it for them. That's how open source works : )
This repository contains the mnemonic list in different languages (Currently just 8). There are also wordlists in other languages that are stuck in limbo. However if you find it to be worth it, you might want to prepare a list and submit it to the repository as a pull request, and one day it might get merged.