Balanced means that it has carbs AND fats AND protein, all in reasonable proportions. I.e. proportions recommended by most nutritionists not committed to one particular style of fad diet or another. As an example, a diet that prohibits or severely restricts any one of those three broad categories is not balanced.
So balanced isn't an objective description but totally subjective. "Reasonable proportions" and "proportions recommended by most nutritionists".
Only in diet and nutrition does a majority opinion define what "balanced" means.
BTW, there is always an alternative to eating white bread and other simple carbs (or even meat for that matter). It's called not eating them.
It's called a consensus. Not exactly unheard of.
Technically majority opinion is not necessarily the same as consensus
And "balanced" is not defined by consensus or majority opinion (except in diet and nutrition).
It's become one of those feel good words that has lost it's original meaning and just means "we like it" (in diet and nutrition).
If a diet were 33% Fat; 33% Carb 33% protein, that could be considered balanced, but the consensus and the majority opinion is that's too much protein, unless it's a high calorie diet, since the optimal amount of protein is based on weight, not a percentage of calories.
If a diet were 20% fat 60% Carb 20% protein, that could meet the majority opinion about what's "balanced," but by any reasonable definition of balance, it's way out of balance. Particularly considering that fats and protein are essential nutrients, but carbs are not.
Also, while those proportions are within the dietary guidelines for macronutrient proportions, there is not consensus that it is "balanced".
But saying "balanced" is whatever the majority opinion or consensus among experts say it is, doesn't answer the question:
What proportions are considered balanced? If you're able to look at a diet and say "That looks balanced" then you must have criteria, right? Or is "balanced" like pornography, can't define it, but know it when you see it?