At no point did Bungie specify you'll be God mode against low levels. If both of you were meleeing each other, you'll find they'll need more hits to kill you, than you killing them. That's already a huge advantage. I've also seen low levels unload their auto rifles at me while I two-shot their body with my hand cannon. In normal Crucible, I'd be dead. In IB, them missing a few of those shots makes a huge difference, and those are differences that are clearly seen with the level differences, and personally, they feel right. Now against a lower level 20-22, you'll notice an even greater difference. Now again, if anyone gets a full Fusion round into you, it's going to be over. So, get good at dodging Fusions and not run into their faces when it's charging.