Why do Americans seem to complain about cultural/behavioral differences with Desis more than they do about East Asians, Hispanics, and Middle Easterners?

I often see that when Americans talk about Indians and Desis in general, especially online, they talk about encountering cultural differences, and the tone they mention it in often sounds like they are frustrated. They talk about caste, sexism, haggling, body odor, not tipping, etc, and advise Indians/Desis to stop this behavior. While this may be good advice on its own, I don't see Americans complain as much about East Asians, Hispanics, and Middle Easterners, apart from complaints about Chinese students cheating. In fact, they seem to be pretty willing to overlook differences with these groups in a way they are not for Desis. And I see people from all backgrounds making these comments: doesn't matter if they live in rural Kansas or suburban Bay Area or Downtown Brooklyn.

Why do you suppose this difference exists? Are cultural issues of Desis TRULY on a worse scale than those of other groups? Or do many Americans have preconceived dislike of Desis more so than towards the other groups?