From when i was into sport atvs. Aluminum skid plates were ok.... If super thick but still took a hit and stayed bent. Had an aluminum skin on a banshee, big dents, bent a side into the brake and had to pry it down. Had a plastic one on my predator, some scuffs but always kept its shape and no bent rotors or rings.
Also an aluminum ring guard on a pedal bike is known as "light duty" dh bikes have plastic to bash rocks and not worry about bends.
I typically agree with that statement however this time around it's an extrusion and pretty thick. I don't see you denting this skid unless you hit a rock.