Depends on how you define "world changing" I guess, but this world already looks different to the pre-LLM world to me.
Me asking LLM's things instead of consulting the output from other humans now takes up a significant fraction of my day. I don't google near as often, I don't trust any image or video I see as swathes of the creative professions have been replaced by output from LLM's.
It's funny, that final thing is the last thing I would have predicted. I always believed the one thing a machine could not match was human creativity, because the output of machines was always precise, repetitive and reliable. Then LLM's come along, randomly generating every token. Their primary weakness is they neither precise or reliable, but they can turn out an unending stream of unique output.