I find myself unable to loot world boss chests. I do not even get a ‘press x to interact’ cue.
Possible contributing factor: pact autoloot mastery achieved. I had the suspicion before, but most of my characters carry too much stuff around to immediately notice, but I went on 2 x shatterer (different computers) and 1x jungle wurm on a toon with a near-empty inventory, and it was quite clear: no boss chest loot (no dragonite).