MarkB
Legend
I feel a disturbance in the Force, as though thousands of voice actors had suddenly cried out in anguish, and been suddenly silenced.I don't know if it's true, but folks on Twitter claimed that Luke's voice wasn't genuine Mark Hamill, but rather an AI-generated voice trained on audio books Hamill had read. That would explain the uncanny (as in "uncanny valley") acting.
But more seriously, I find that a little unlikely - it's something that might be done to recapture the voice of a deceased actor, if the technology is there, but Mark Hamill is still around, and still perfectly willing to work on Star Wars projects.