Well, most Pakistanis aren't "obsessed" with race. That's an Indian thing probably driven by the caste system which is rooted in an inferiority complex to the foreign light skinned invaders who established themselves as upper castes. Really, Indians are just projecting their insecurities of viewing Pakistanis as "superior" fairer people when they make comments that we claim to the white.
Pakistanis have different beauty standards and are generally attracted to their own race. That's not racist.
Secondly, while she is very crude in her expression, let's be honest, it's the thought process one has when seeing a very unattractive person, especially when being asked to marry them- doesn't matter whether the thing you find "ugly" is flab, acne, skin colour etc. Some filter their thoughts and politely reject, while blurt it out rudely. Girls might not want their kids to look like what they consider "ugly."
It is not the fault of Bengalis that they are dark or short, nor is that neccessarily a bad thing IMO. However, beauty standards are different eveyrwhere (being morbidly obese is attractive in an African tribe). Pakistanis naturally will be attracted to people of their own race/look. Even in India the top bollywood stars are light skinned and there is a fairness cream craze. So while there's nothing wrong with considering a skin colour/race unattractive, there is no need to be so rude on camera to them. It's wrong to make others insecure over traits they cannot control.