Why are racist terms amongst adolescence not seen as that serious?

the only really racist or insensitive things i have gotten for being mixed race (jamaican and peninsular Spanish) have been being called “blackie”by people in my small white town here in spain (there are no black people here).

usually with my friends or mostly popular people they’d called me “blackie” as a joke or pointed at any black thing and said it was me, which sometimes bothered me since it was a daily joke used on me but i laughed with them since i insinuated it was just a simple “joke”.

i also got called “blackie” buy a guy and his friends who i used to be romantically involved with (the guy) , and they’d talk bad about me and call me derogatory names while i wasn’t there, just for simply being mixed race.

why does this happen? in the adult world saying something like this is “forbidden” or “taboo” since it’s extremely racist, but amongst teenagers if you complain you’d get name-called.

Why are racist terms amongst adolescence not seen as that serious?
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