That's a really interesting, and worrying, article.
I think that the children of these conservative groups are being failed, with families allowed to deny them opportunities which other British children enjoy - the right to a good secular ducation, getting to play sports, forming friendships, and then arranged marriages, to bring other family members over, and the problem with intergenerational cousin marriage.
I think schools dropped the ball big time, for fear of being racist, they accepted the restrictions which parents put on their kids, allowed kids to be put of school for months at a time, as families returned to their home countries.
The lack of integration seems to have been ignored, and the develooment of parallel commumities not seen as a problem, in part as no one seemed that bothered about how long the seperation of communuties would continue, maybe policy makers thought the second generation would fully embrace being British, because why would they not? When they didn't, no one really cared - the left was very concerned about respecting people's culture and religion (regardless of whether it stifled human rights of women and children) and the right happy to have seperation of communities, as they didn't see the immigrants as British, but handy for cheap labour.
And of course decision makers weren't living in Bradford or Luton, so easy to ignore what was happening on the ground.
I don't know how things can be change except possibly through education, though challenges to the commuity culture can have significant push back from the wider commumity eg sex education in schools in Birmingham.
If community leaders worked to support integration it could help, but commumity leaders are older relugious men, they're the ones benefiting from the status quo.
Commumity members who challenge the status quo can find themselves rejected, and if they are, they leave.
The issue of self-segretation is a really tricky one - it's not just Pakistanis from this region, Travellers and Roma have similar issues with self-segregation, but it hasn't become such a big issue, as there seems to be more of a geographic spread, and they have not come to public attention in the way the grooming gangs have put a spotlight on the Pakistani commumity.