Who is at fault here?

There are two passengers in seats next to each other:

X, all alone.
Y, with a baby.

Y’s baby repeatedly kicks X.

X turns to Y and says, putting X’s hand in the middle of the armrest: “This has to stop. The space is here.”, and gestures to the middle of the armrest.

Who is right and who is wrong?

Later, X shows a video on X’s phone: Y calling a fast food employee at their origination airport a racial slur.