New England woods here - I have an FHF harness and it goes with me everywhere, all year. Holds binos (10x50), milkweed, grunt tube, range finder, tags and my havalon knife. It will occasionally bump my bridge in the tree, but doesn't make any noise. It's never once been an issue shooting my bow, and I always practice with it on.
There's not much thicker cover than what we have around me here, but particularly late season, it's useful to be able to look at the opposite ridge, or into the cattail marsh, or even through the cover at something 20 yards away. I've picked up rubs 100 yards away, scrapes that I never would have seen, trails... and of course deer.
I've heard something move and spent 10 minutes methodically looking to eventually see a deer 30 yards away. Would never have seen it without binos. Picking out a rack in a tangle of saplings and brush is really hard without them. Not to mention that at first and last light you can see through good glass when your eyes simply don't have enough light, especially to determine buck vs doe.
I can understand people not carrying them, but to say there's no use for them hunting whitetails is just not remotely true.