Teaching kids to say “I don’t like what you’re doing” (or the specific action) to each other instead of “stop” makes their interactions far more peaceful. It avoids a power struggle where the person doing the action has to decide whether to do what the other said (“stop”). Instead, they now have info they can use when deciding if they want to accommodate the other’s opinion or if they prefer to be a jerk.
My wife is a kindergarten teacher (in Sweden it requires a bachelor's degree, so it's an actual thing) and one of the things she has kept bringing up during her time at uni is that you have to explain why. Just saying "stop", "no", "yes" etc teaches them nothing. What is obvious to us is unknown to them. Explain why and they'll be empathetic back.
I grew up such a people pleaser that this would have worked SO well on me. Stop leads to “why?” But my parent being upset, or god forbid dosappointed… those are some words of great power.