Internal/external balancing

I thought the BHJ dampers were thicker than OE dampers too. Really, any aftermarket damper should be thicker because you can’t make it bigger in diameter, but it throws off pulley alignment.
Why should they be made thicker? The BHJ I have is the same as stock, the fluid damper is thicker but center is stock thickness, the ATI is also the same as stock. Just looked at all 3