No one can tell us what file formats will be available in any future. All we can do is save what we have. For longevity, CDs, DVDs, and Blu-ray are the current media of choice. I say this because even magnetic data such as tape and hard drives have a shelf life. And tape can break, hard drives can crash, and the sun may rise in the west.
What storage device is in the future? One little item is the four quantum states of a special isotope of I believe cesium (don't quote me on the material). It exhibits four states at the molecular level. Storage of unheard of capacity because each molecule can store four bits.
Save what you have to optical media. In any future, if a file format changes, create new files in the new format. If it's available.
I know you're concerned, but you've asked question no one can answer with any reliability.
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