Since nobody explained it yet, the main reason to care about portal axles is clearance under the diff housing. On a straight axle rig that low-hanging pumpkin is basically a skid plate you never asked for, catches every rock. Portals lift the whole drivetrain up by running a reduction gear at each wheel end instead. Tradeoff is slightly higher CG and more stuff to break, but for creek beds and rocky trail stuff like benson creek it genuinely matters