You may not be a native English speaker, so you may not be aware of the fact that we have no gender-neutral, third person, singular pronoun for a person.
This isn't true. There is a gender-neutral, third-person, singular pronoun for a person. In the nominative case, that pronoun is "he". In the objective case, it's "him".
Yes, it's ambiguous that the gender-neutral pronouns are spelled and pronounced the same as the masculine ones, but it's far from the only case in English where we've got two words spelled and pronounced the same that mean different things. I always figured if people wanted to communicate in an unambiguous fashion, they'd choose a language other than English..