correct, you can't simply "Teleport" without literally dying, you are deconstructed on an atomic level, then reconstructed again, who is to say it was the same exact atoms used? even if they were, you are already gone, you are just reconstructed the way you were, but who is to say its actually you? maybe you are dead, and thats just the perfect copy of you.

all in all, if your brain dies, you die with it