Transporters work by de-assembling something (e.g. you) and re-assembling it somewhere else. What if, when you're dis-assembled, you die, and the re-assembled version of you is essentially a copy? Then every time someone steps onto a transporter, their final thought before death is that they'll end up beamed somewhere else. And the re-assembled version (copy) just thinks that everything went fine and continues on like nothing bad happened.
More like: If you replace all parts of a boat with completely new parts, is it still the same boat?
I don’t know if I call it new parts, identical parts definitely. But is something technically new if it’s identical on a molecular level? Blemishes and defects and all.
Well no, it’s the same parts. It’s literally called the matter stream. The exact same parts are taken apart, moved to a new location, and reassembled.