nicaq25,
He compared the average salary of all British who answered the survey with the average salary of all Indians who also answered the survey.
Because of the diversity of grades is greater among Indians than Brits and the distribution among those grades is not equal between those two nationalities, the analysis of the Survey data can NEVER be accurate unless the comparison is done between nationalities AND within the same job grade.

The article’s title was taken from the mishandling of the data, either by ignorance or by malicious intentions to provoke polemic (to sell). Considering the quality of journalism in this region, I suspect the second scenario did take place!