No there isn't a single depiction in BW that's relatable to 2nd or 3rd generation Desi's.
NRI's depicted in BW are complete aliens whether it's speaking, behaviour, family dynamics, even clothes.
Religion and culture are 2 separate things as many have pointed out. There are so many 3rd generations who actively partake in religion, whether it's joining the youth groups at Hare Krishna/BAPS/other sects to raise their spiritual and religious knowledge as well as charity work. However, so many of them wouldn't be caught dead watching a BW movie.
Even as a second generation desi in the UK, who's often labelled a coconut there's definitely a difference between me and third generation Desi's. Moreso their willingness to learn Gujarati/Punjabi/Urdu at a Saturday school and actually undertake it as a GCSE (10th equivalent in India) and proudly flaunt this on their CV/LinkedIn. If that's not pride, I don't know what is.
3rd generation Desi's whose families immigrated from Kenya/Uganda in the 60's/70's tend to oscillate between extremes; either really traditional or so far removed from their roots (Priti Patel springs to mind here who acts even more colonial than the British).
There's so many variations of NRI's that no one has even bothered distinguishing from- Mississippi Masala did a good depiction of an Indian family kicked out from Uganda under Idi Amin and then Brick Lane, but they're not BW.
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