In context of this reality show the term “Class” is neither in reference to the education/degrees that you hold nor the income that you earn, rather it refers to the way a person is conducting oneself. How much ethically and graciously one present’s oneself against all the odds determines his or her class in personality based reality shows. Therefore if viewers say that Rubina is more classy in comparison to other contestants that means that her mannerisms and conduct is more likeable in comparison to others. Hence superiority complex is a totally different term in no way related to class in present context.
Brilliantly explains it!
In respect to the BB house, I don't think anyone is talking about education or the socio-economic background the contestants are from. When I say I like a classy contestant, I mean someone who carries themselves with grace, not gross, respectful, etc