Personally, I'm not that bothered.
But it is definitely true that the percentage of people wearing red in the ground is significantly higher than it was in the past.
Many people just wouldn't consider it. Not in a "Look at me, I can claim to hate them lot the most" style. More that red is the colour of City's rivals and, particularly in sporting environments, where colours around the stadium and that people wear make a contribution to the environment, it stands out as such. Add in that it is usually a very bold colour and you'd have to be a head in the sand merchant not to understand why, historically, people wearing large red items have always been very rare at City games.