I know one thing. There people on this board that don't know physics.
Drag is caused buy friction.
When casting spinning reels the line loops down, making contact with every eye of the rod,friction!
You will say that there is more friction in a bearing,Granted.
On the scale that is used for bearing is a scale on 1 to 9,by two's
1,3,5.7.9. 1 being the softest.
The hard the bearing. The harder it's for the friction to cause heat. Less friction= less drag.