Wheat is nutritionally very poor, especially when it is processed into bread. The caloric value is immense though for what you are getting and for how fast you get hungry. What you get is greatly reduced by processing and natural and artificial add ons that prevents absorbtion of nutrients since the grain was not designed by nature to be digested. It was designed to be pooped out. Legumes, millet or buckwheat cooked in a traditional way, quinoa... I can see the argument there. But bread is only good for those poor folks who can't gain weight at all. Maybe not even for them. I mean, if you ground your own flour, and baked it without any artificial crap, unleavened, and you had no way of obtaining calories any other way... bread/grain is a starvation food.
Look, it's so easy to see if you are better or not without grains. Just don't eat it for 6 or so weeks, and see if you have a positive difference. I noticed it on Day 2 of dropping processed grains (I was still eating traditional cooked cereal and legumes). It was ridiculous, how much better I felt and how much less I ate.
But you maybe one of those wondrous people who can eat half a muffin for breakfast and toss the rest in the garbage, then have three macaroni's with half a slice of cheese and an apple for lunch and maybe a toast for supper with a smear of peanut butter, and roll on happily saying how they are not hungry at all and how meat has a disgusting texture.
So, experiment! All the science in the world is pointless if you do not know because you have seen it.