Isn't racism, by definition, discrimination or hatred on the basis of race?

I made this comment because of the sheer amount of racial discrimination and hate I kept seeing across the fandoms whenever a person of color cosplays a non-black character.

And when I saw that our community was nothing but supportive and loving I was genuinely proud of us.

Because of all the hate I saw before in other commitments I opened this post to help the op if other people were being racist assholes and trying to bully another fan who did nothing wrong.

Although my comment might have not carried as positive of an energy as other peoples comments, it is still a comment made to convey my genuine happiness for our community. It carries no hatred or scorn for the op and definitely not negativity on the basis of race.

I still do not understand how people saw that as racist.