Ok actual wild guess but also not so wild(I thought about dedicating a thread to this) The weird canister thing on Link's hip is our new magic system. Runes/magic abilities will be fueled by this magic making them slightly less reliable and we'll have to keep our magic filled. That's why we...
The end of the game will depict the beginning of Skyward sword and we learn that TotK is simultaneously the first and last last game in the time-line, making the time-line a repeating loop.