There are a billion reasons, but this video shares some. “Sex & Circumcision: An American Love Story by Eric Clopper”
I also like to cite that it only started to reduce the pleasure of men in America, at a time when a similar practice was started to stop “self-abuse” in women.
https://en.wikipedia.org/wiki/History_of_male_circumcision#Masturbation_concerns
And that it is rare around the world, except in less developed countries (mainly in Africa and the Middle East.)
https://en.wikipedia.org/wiki/File:Global_Map_of_Male_Circumcision_Prevalence_by_Country.svg
And I like to talk about how it messed up David Reimer’s life.
I have a ton more arguments, but those are some of my favorites. It is an unnecessary invasive procedure, and no children give consent to have their genitals mutilated before the age of consent!
Props to Andrew Yang for criticizing this practice.