I think it important that the ancient songs should be performed as near as possible to how they would have been originally.
-VirginiaTam

And there, in a nut shell, is the difference between African/African Diaspora singing and European and European Diaspora singing.

I know I'm generalizing, but for the most part, African/African Diaspora vocalists place a high value on interpreting a song, thereby making that song their own. In hip hip languaging, this is called "putting your flava into the mix".

But, that said, I understand that there's one school of thought in modern jazz (among Black musicians as well as non-Black musicians)a as to whether jazz artists should strictly play music that has already been composed or whether they should interprete it their way and (as we used to say "jazz it up"), though maybe "jazz it up" means play it faster.

The concept of the "remix" in hip-hop" and other music is all about having another version of the "original" song...
   
[I understand that my comment has very little to do with the thread's topic about vocalists making "exaggerated vocal and facial expressions". But I wanted to share these thoughts anyway.]