McCoy's teasing of Spock is racism, because it concerns his race's appearance.
No it's not it's just that teasing. McCoy only teased Spock, never made rants about Vulcans in general or said anything negative about other Vulcans he met.
McCoy also seemed fine with Vulcans in all other interactions, it was just Spock the individual that he needled. I think if there was any racism, it was the half-Vulcan race, as McCoy was truly a man of emotion, and the idea that any human, even a half-human, would so entirely reject all emotion was what really got him upset.
I remember one episode in particular (can't remember the title), Spock got taken over by an alien super-power, and the super-power liked the idea of invading Vulcan and turning them into warriors. McCoy looked aghast and emotionally shouted, "You can't! Vulcans value peace above all else!" He spoke as someone who viewed the Vulcans as members of his family (the big Federation idealism family-kind) and respected them and their ways.
It was just Spock the individual that annoyed the living hell out of him.
I always thought a great TOS episode would have been one where a full-blood Vulcan served aboard the Enterprise temporarily, and Bones got along with him swimingly, probably more so than Spock would.