I’ve been watching the TV series Pantheon and I really like it, but this tiny aspect is something I can’t quite grasp. So these people have their minds uploaded to the cloud - and they make a point to state that they’re still “them” - alive, real, authentic. But would it really be like that? The process is brain mapping, so essentially they just make a perfect clone of your brain/mind and run it digitally. But it’s still just a simulation. A perfect clone is still just a clone. The original person is gone. I don’t see the “continuity” aspect.
It’s not exactly the same physical brain though? Neurons die and are sometimes, if rarely in adulthood, generated. They are constantly repaired, the exact molecules that make them up change. Glial cells die and form and they have supporting functions. Diseases change brain structure more slowly than immediate trauma. And so on.
I certainly wouldn’t say I’m the same person I was as a toddler.