Let's call it tribalism instead of racism.

There is no such thing as 'race' - but teams, groups, tribes, etc are all "real" - yet social constructs. Let us accept now that in future humans will laugh at the word 'race' and never use it - when considering our present-day 'races' they will see them as no more than 'tribes' determined by allegiance not biology - allegiance determined usually by indoctrination, moreover, not (moral) choice, not reason.