It has been spoken by a significant portion of the Jewish people for 1,000 years. It was once the trade language of the Adriatic Sea, the Balkans and the Middle-East and renowned for its rich literature especially in Salonika [Wikipedia]. A major commentary on the Tanach Me’an Loez was written in it. There is evidence that at least some of the chochmei Tzefat spoke it (although the Arizal was careful to only speak Hebrew, even with his wife and Rav Ovadia says that in the bet midrash they all spoke Hebrew).
It is a huge shame that only in recent decades it has effectively been given up after having served as a holy Jewish language for so many centuries, as you indicated.
Loshon Kodesh has by design NOT been utilized as an everyday chol language by Klal Yisroel for thousands of years.
I heard that certain Turkish kehilos of Spanish or Portuguese origin recite the Brich Shmei during Pesichah in Ladino. It begins “Bendico sunombre”, if I recall correctly.