It may be commonly accepted but it is based on data which doesn’t say what people think it says. First of all, MIT does not admit by major. So whether you intend to major in Poli Sci, Linguistics, Econ or Engineering- you aren’t getting a finger on the scale based on your stated interests because that’s not how they admit. And second- the “finger on the scale” at schools which do admit by major is a very, very light touch. It might be marginally relevant at RPI for example– but Princeton doesn’t need to worry about its gender balance- there are more than enough qualified people, regardless of how they identify- that they can ignore the who/what.
Apply as the person that you are. I don’t think there’s an advantage AT ALL to obfuscating the issue.