There may be two main reasons why Marvel Studios has changed Namor’s home to Talocan. Firstly, they may want to avoid copying the Atlantis shown in the 2018 DCEU film “Aquaman,” and secondly, they want a locale name that is more consistent with the heavy Mesoamerican theme of the MCU’s Namor (Talocan might be inspired by the Aztec Tlālōcān).