We're not all as progressive as you.
1) Part of your language and culture involves the use of terms that have always been funny and relatively harmless to you;
2) As it turns out, the use of those terms has been demonstrated to have major psychological consequences for a pretty large segment of the population;
3) The severe damage done by the use of those terms is widely recognized and acknowledged. As a consequence, the use of those terms is no longer acceptable in public discourse and is commonly frowned upon in private discourse as well;
Your possible responses:
a) Acknowledge the damage done by the language and make an effort to change your own habits in private and public;
b) Assume that no one you have private conversations with could possibly be hurt by such language and thus try not to use the language in public but don’t worry about it in private;
c) Ignore the fact that language has the capacity to do major psychological damage and get angry when people suggest that you might consider toning it down.
You choose c. Cool.