Being repelled by a person on the basis of some physical characteristic is fine and normal.
the problem starts when people take - or -don't - take action that affects that person, I think
I think it is when you blame the person for the reaction. If I have a negative reaction to someone being left handed, I cannot help that and should not be blamed for it. If I blame the left handed person for that negative reaction, then it makes sense to be annoyed at them. If I realise it is just a daft reaction, then I would have no reason to treat them differently. Self awareness is the important thing. Personally, I am rubbish at self-awareness, so I am just lucky that I do not feel particularly repelled by other races of cultures rather than being morally superior.