That video is dumb, sorry.
Tina Turner, Janis Joplin and Christina Aguilera have just different vocal types, which some people perceive as screaming.
The only one who is really screaming instead of singing is Jessica Simpson.
I could listening to Xtina every second of my life, while Jessica Simpson's voice hurts my ears terribly.
Xtina is the reason for words like Eargasm
And she's known for her title as:
The Voice of the Generation
praised by a lot other singer and music professors!
It's just a dumb trend to say Christina is a bad singer.
That trend started shortly after The Fame was released....