Apart from Prof. Howard Resnick's analysis, the following from  Prof. Jesse Knutston also deserves attention:
 
when in fact the IVC was a highly developed civilization, of greater
antiquity than the Veda, which did not speak an Indo-Aryan or Indo-European
language. To attribute the IVC cultural achievements to the speakers of
Vedic is extremely racist and chauvinistic.

1. 'IVC was a highly developed Civilization' has the following assumptions : a. civilizations are superior to non-civilizational cultures. b. IVC has that superiority of being a civilizational culture. This is confirmed by the expression 'IVC cultural acievements'
 
2. 'which did not speak an Indo-Aryan or Indo-European language' has this assumption: The language spoken by the IVC people is clearly, undisputedly known through the decipherment of the seals and other such 'written' evidences.
 
Assumption under 1. is racist, evolutionist and has urban chauvinism.
 
Assumtion under 2. is in contradiction with the fact that the language of the IVC speakers is still under dispute and not yet clearly established.
--
Prof.Nagaraj Paturi
Hyderabad-500044