This movie doesn't promote girl power at all actually. *Spoilers.
Think about it. Captain America was clearly more powerful than Thanos. Yet he still kicked her ass because he was a better fighter. He was too smart and quick. She couldn't really lay a hand on him.
She had all the power in the world given to her and she still fucking lost. To a man whose talents came through years of hard work and training. Whose the strong character in this situation? The man.
The girl power moment wasn't really earned in this movie. The only strong woman was Black Widow because she literally sacrificed herself to save half the universe.