Short answer is yes.
 
I don't know for sure where the actual iCX sensor is located, but I believe that the primary "GPU" temp displayed in HWInfo or Precision or MSI Afterburner, is perhaps an edge temp or not so much towards the center of the die, whereas the GPU2 temp is either the backside of the die area (which will be almost as warm as the actual center of the die) or near the center of the die itself.
 
Even at idle, mine is almost always 1-2C higher on GPU2 than GPU primary.  At load (keep in mind this is on a Kingpin, which also has additional heatsinks placed on the backplate above the GPU die area so it has better than normal heat dissipation), my temps vary around 2-5C between them. 
 
As an air-cooled example (in a well ventilated case with good airflow etc), my 3080 FTW3 Ultra in Port Royal had a 55C max load temp on GPU, GPU2 peaked at 61.4C - so about a 6C difference.  
3090 FTW3 Hybrid at a pretty hefty undervolt in Cyberpunk testing had a 7-9C difference between GPU & GPU2 in separate tests I ran.  So it does vary a bit.  I probably could've lowered that by redoing the paste etc, but I didn't bother with that.

Ciddharthas
I've noticed that my GPU2 temp is almost always something like 5-8 degrees hotter than GPU1.  I installed a hybrid kit a little while ago (on a 3080 ftw3 ultra), and I'm not sure whether it was doing this before or not (when it was air-cooled), since I guess I wasn't paying as much attention to the various temperatures temp sensors aside from the main one until after I installed the hybrid kit.  I'm just wondering if this is typical or not.

It gets warmer because it is located PCB side of the card where you install the back plate for the Hybrid kit. It is normal for it to be hotter than 5C to 10C. I would suggest to have some kind of fan blowing on the back side of the card. Mine has dropped from 8C+ down to about 2C with the GPU1 temp since I put a waterblock on my card and a nickel back plate.