Electric motors are cheaper, smaller, and simpler devices than ICE engines.

Two electric motors probably is cheaper - both in parts and assembly steps in the factory - than one motor plus a transfer case / center diff, a driveshaft, and another rear diff.

Electric motors are small and can be packaged down near the axle, so the rear motor doesn’t take up all the cargo room.

The place the driveshaft would go through is also the best place to mount the battery pack. So no driveshaft means better packaging for the battery.

Also you can use two smaller electric motors to get the combined power output you want, rather than one large motor that has to produce all of that power and then deal with drivetrain losses from the AWD system.