Similarly, it's a "complete" protein, whereas most vegetables and legumes are missing necessary amino acids.
The downside of beef isn't the "density" of nutrients: the downside is high saturated fat. Chicken breast, though, is similarly high in protein without the saturated fat downside.
So the problem with steak isn't the steak itself it's the "steak dinner" where the meat comes with sides such as french fries and drinks such as beer.