Complex sentence: Since there were other affordable handhelds and the TG-16 was not popular enough to be accessible for the great majority of players, the system was finally quietly discontinued around the time the Turbo Duo was also in its twilight.
Split into simpler sentences: Since there were other affordable handhelds and the TG-16 was not popular enough to be accessible for the great majority of players. The system finally was quietly discontinued around the time the Turbo Duo was also in its twilight.