As I heard it, they wrote the script without concern for the gender of the actors, and they picked actors for the parts based on auditions. Although commercial reach reasons would also fit.

SPOILER ALERT: At the end of the day, it still fits the meme:

"Alien is a movie where nobody listens to the smart woman, and then they all die except for the smart woman and her cat."

If her character was really empowered, maybe they'd listen to her?

/SPOILER ALERT