That's a proxy for socioeconomic inequality. Now what you are trying to argue is that Americans just might prefer action films. Ok... great. Americans prefer action films. But why?
So we go out there and we ask Americans how they feel about documentaries:
"They are boring. We'd prefer not to watch them."
Hypothesis confirmed! So we ask them why the prefer action films: "Because they are in English. All the good documentaries are in Spanish."
Ding ding ding! Of course Americans prefer action films! They don't have access to good documentaries! Why would they prefer documentaries when they are all in Spanish?---
So when you ask why women prefer not to work in STEM, you'll learn something about the cause of the social inequality. Saying it's a "matter of preference" tells you nothing. It just sounds like you're trying to invoke a naturalistic fallacy and stop investigating.
Maybe if you invested more in good English documentaries, they would be quite popular. Maybe the preference would disappear. So it doesn't matter if there's a preference. What matters is why there is a preference.