Just posting briefly to agree that: (a) language interests generally don’t serve as a “hook” in the sense selective colleges would apply a lower admissions standard; but (b) language interests if well-developed into something bigger can be part of a cool story that helps build a general admissions case.
As others have suggested, language interests can be part of a broader interest in really learning about other cultures, other countries, other histories, other great thinkers, and so on. I think lots of colleges value people who are intellectually ambitious in that sense, who are looking to college for opportunities to massively expand their access to different perspectives and experiences.
So being able to paint an honest, enthusiastic picture of yourself as an applicant like that might well be helpful. And a language interest could obviously help to that end.