https://singularityhub.com/2022/08/28/this-newly-discovered-super-earth-may-be-an-ocean-planet-shrouded-in-the-deepest-of-seas/
I would say 50/50
Wrong Cameron movie.
I'd say not even 1% earth covered in ocean in the near future... I'd worry more about other movies predicting our future, like Idiocracy. An average movie from 15 years ago is getting scarily close to reality now.