Hagia Sophia has held different importance throughout history as outlined below:
It was considered the most important Eastern Orthodox cathedral (532-1453 AD).
It became the major mosque of Istanbul after the Ottoman Empire conquest (1453-1935 AD).
It became a museum during the presidency of Ataturk (1935-1986) & after that, it is presented as a museum.
It is currently functioning as a mosque after Turkish state governance in (1982-2020).
Hagia Sophia will remain important throughout Eastern Orthodox, Roman Catholic & Islam cultures.