https://www.descript.com/lyrebird-ai
Alexa can already talk like Samuel L Jackson.
https://www.amazon.com/Samuel-L-Jackson-celebrity-voice/dp/B...
It's a risk, but to me it's also a part of living in this century. Human voice impersonators have always existed. When Photoshop became a phenomenon, everybody knew that photographs could be manipulated. SFX departments have always been able to produce fake scenes -- and now with deep learning, more people are able to do it (albeit somewhat badly). Not advocating that anyone feeds training data to voice assistants, but in the end it's a personal decision based on what you value.
For me, it's impossible to uninvent technology, so all we can do is to manage the risks.