[Texasian]

That’s because film actors are hired to voice act for their fame, not for their skills as voice actors.

[nomel]

Yes, and another example is that sometimes the “skill” of a voice actor is having pleasing vocal cords. Again, this is why most narrators are hired: they sound good. Not all voice actors are chameleons. It is not a requirement for all voice acting jobs. If you listen to many audio books, you’ll see the voice actors usually have very very poor ability to modulate their voice. Laughably so.