I voted against Tav voice acting. For me it's a matter of pacing.
I am given dialogue options, after reading them and deciding what I'm gonna say, I don't need to hear it read out for me, and would rather not wait 3-5 seconds before hearing the other side's response.
I enjoy the more immediate feedback.

As for dialogue that wasn't an option I made but rather something Tav decides to say on their own, I would prefer if that was voice acted....

I also wish Tav had extra voice actor options to choose from.