when a boomer says something stupid and completely wrong you say this as a way to say "you are completely wrong but i don't want to waste breath on explaining something obvious that you won't even listen to"
Boomer: Back in my day, we ate pie made of mud and laundry detergents, drank bleach, and broke into power plants, but people nowadays are saying that is not socially acceptable!
Ok boomer is something you say to (specifically a boomer but could be anyone) a person says or does something very outdated. (Like taking a selfie with a camera) ok boomer is specifically a Instagram, Snapchat or tik tok thing, but is often said irl