The 'R' key moves all of your inventory into whatever chest you are interacting with, including random chests you find at POIs in a random realm. In my opinion, this is a terrible key assignment, and as far as I can tell, cannot be reassigned.
If anything, 'R' should be a TAKE ALL key to quickly loot everything, but why would I ever want a 'put all of my inventory into this one container' hotkey?
Or make R move into a chest, and L move into inventory.
Even better if plain "R" and 'L" mean "Equivalent" and "Shift-R" and "Shift-L" mean "All"
And the poster with the Steam deck is totally right. It's even worse on deck. than with a keyboard and mouse.