You can always slip off the belt for the supercharger and turn it by hand to see if it is showing signs of bind by hand.
An alternative to look at is maybe the bearing on the AC clutch bearing is bad.
I have a 2004 Monte Carlo with pretty much the same supercharged engine. At 45Kmiles the belt tensioner has siezed causing the belt to be overly stiff. What happened next is the AC bearing took the abuse that the belt tensioner is supposed to absorb. This beat the bearing out on the AC. Now the noise was what I thought a bad supercharger until I looked around. I was able to find a replacement on RockAuto.com that was very simple to change just the pulley and bearing assembly.
On a cold motor, reach down below the coil packs and see if there is any side to side wobble you can create on the AC pulley. Or even just look down at the pulley while the engine is running to see if it is moving around a bunch.
And yes the compression ratio is a 8 to 1 instead of the 9.5 to 1 on the non-supercharged cars. That will result in a very weak car if you disable the supercharger and replace with a non-supercharged assembly. A possibly alternative, is to take the belt off the supercharger and find a way to block the bypass valve located on the front of the engine at the supercharger base in the always bypassed mode. That would be when the vacuum has pulled in the actuator for reference.