Depends on the context. Are you copying someone else’s identity in order to make a passable clone? Are you trying to sell that clone?
A duplication of someone’s voice, commercialized by an unauthorized source, is definitely a form of stealing.
Copying information illegally, such as private information held on a private device, is overwhelmingly illegal.
In general, copying information is only as legal as the purpose behind it.
Soyjak: Pizza toppings are gross! I just eat the materials raw!
Chad: Eat what you want, how you want.
Edit: I just realized, this isn’t political enough for some people (non-Italians). Imagine Pizza is a metaphor for cannibalism. There, it’s now political.