I think the correct term is "bearing drag", not bearing "friction". Friction would implicate 2 surfaces contacting each other and if that was the case there would be no place for oil, and as such, you would have a very noisy bearing.
Furthermore, a well made bearing would have a hardened shaft, be cylinderically ground, and the bearing housing would be honed to accept the rotating shaft with perhaps 0.0001"-0.0002" clearance at most.
Furthermore, a well made bearing would have a hardened shaft, be cylinderically ground, and the bearing housing would be honed to accept the rotating shaft with perhaps 0.0001"-0.0002" clearance at most.