there is no "default editor" in unix systems per se, only installed by default. whatever the user/distribution sets in $EDITOR/$VISUAL is the one being called.

there is no "default editor" in unix systems per se, only installed by default. whatever the user/distribution sets in $EDITOR/$VISUAL is the one being called. vi/vim became "default" on linux distros because it was simply always available while emacs was an optional kitchen sink package and there were no other widely accepted alternatives (like midnight commander's built in editor or nano).