Video comparison of art vs. reality
First, Malek is too slight. Freddie had broad shoulders, and it really added to his presence on the stage. But if you just fell from the sky and watched the two performances, you could easily see who was the imitator, which one commanded the stage, and for pity's sake, there was one point where Freddie is using the mike and part of the stand to pretend it's a guitar while Malek doesn't seem to know what he's doing with it.
Yes, the direction in the movie was a little lacking. Direction can make the difference between something having power, and the audience being distanced from it. The direction distances the audience too much, and you can see in this clip how that subtracts from the impact. More cuts of closeups would have helped. But while Malek was learning movement and mannerisms from a coach, he should have learned what made all the difference -- when Freddie walked on a stage, he owned it. Malek needed to learn how to project that, or he'd always seem like an underweight Freddie Mercury imitator.