Okay so most of us young people currently in high school are living through an age of, I guess, “Modernized Social Reform” lmao. I personally have been involved in peaceful protests for the lives of young black teens and feminism…despite being a male. Anyway, my question is; Will mentioning social activism hurt or promote an application to a top tier school?
I imagine it can do both.
It’s probably a positive as long as you don’t come off as dogmatic or sanctimonious in your app. Being involved in the world and showing engagement and commitment are good things. Good on ya.
It’s a part of who you are, so describe why you decided to get involved. Avoid speaking in !!! 
but colleges like young people with convictions who “walk the talk”. There are very few choices that would be negative (ie., KKK, violent/terrorist groups, etc.)
Agreed, it is part of who you are. If there is a school out there that thinks it is a negative, then it probably isn’t the right place for you anyway.
You’ve just been involved in protests? Or you have done something more fr those causes? That can matter.