The bearing should not be shimmed down and a lift does not wear it out faster.

That portion of the driveshaft is designed to basically be an extension of the transmission output and should remain directly in-line with it. If you shim it down it may vibrate.

The double cardan (CV) joint in the shaft just after the carrier bearing takes all the angle of the lift. The carrier bearing doesn't know the difference. Your lift kit should have kept the joint at the differential more or less straight by pointing the pinion at the CV joint.

And FWIW, if the bearing still spins smoothly (the bearing is good), I wouldn't bother replacing it yet. They are fairly pricey. The play in soft rubber mount is normal (that is what provides the isolation). The separation from the rubber isn't "good," but it shouldn't hurt anything either.