Do you think this is racist? A mini rant

So I always kind of have this debate with close friends to kind of play devils advocate. I know this has been discussed in the comments section of many verge articles. I believe a lot of the time in society that people that actually claim something is "racist" make it racist. Check out this short clip from The Big Bang Theory

The.Big.Bang.Theory.S04E12 - Raj's in chart of phone support (via Duc Anh DC)

For those that don't want to watch or can't. Basically, Sheldon assigns Raj the job of tech support for the app they are creating. Raj immediately says "kind of racist don't you think?" I feel like at the exact moment Raj made a joke about it being racist it became "racist". It wasn't necessarily Sheldon's prejudices that made it racist. In this example it is obviously meant to be a joke but the fact still remains that Sheldon could have simply just assigned Raj the tech support duties. My argument is that Raj and his preconceived notions about his own race made it "racist".

Thoughts? I always have this internal debate and I feel like this Big Bang clip does a really good job demonstrating what I am talking about.