Starting with this, Spanish language is gender-nominative by default. We have, in some instances, deal with gender nouns when available, when in English, that's not necessary (at least, in situations like that). As an example, the word 'engineer' can mean any male or female; while in Spanish, we have to point exactly what one means. However, in formal terms, the gender is meaningless.
So what's the point of this? Some people, like that girl, is overreacting on topics like this. From times and times ago, the term ingeniero, is always used in formal documents like a diploma, but it doesn't address to a gender in particular. However, some people like her, doesn't get that. Because of that, feminism is misunderstood.
Also, this is why I prefer egalitarism.
Answering the question, sexism is on an only place: on some people's minds that doesn't what feminism really means. Persons that think there's a patriarchy because of a (simple) male noun.
So this is what I believe in.