There is such as thing as "positive racism". Similar to the concept that some Asian students internalize that "they should be doing well in school because they are Asian". Just because a depiction could be positive doesn't mean it isn't racist.
POSITIVE RACISM??!! Dude, you're creating a concept that doesn't exist. You're mixing the meaning of the word racism with representation.
Racism
prejudice, discrimination, or antagonism directed against a person or people on the basis of their membership in a particular racial or ethnic group, typically one that is a minority or marginalized.
"a program to combat racism"
Representation
1.
the action of speaking or acting on behalf of someone or the state of being so represented.
"asylum-seekers should be guaranteed good legal advice and representation"
2.
the description or portrayal of someone or something in a particular way or as being of a certain nature.
"the representation of women in newspapers"
Racism is the negative representation of a group of people.
Representation can be done in different ways, which can be negative or positive.
Racism is purposefuly negative, it is done to cause harm, to discriminate against others.