You are changing the question to “is a perfect replica of a person considered the same person or not?”. That is not the question.
What you experience by using a teleporter is you enter a room, and then you die. End of story. There being another replica of you somewhere does not change that you died. For an outsider they may argue whether or not you died, whether or not the replica is you, and so on. But from the perspective of someone who enters the teleportation room, it’s over. Dead.
Math-wise, it won’t take long until they are tied to the track with us and everyone else.