Yes, high trust societies are where you have one ethnicity in general, from observation
Like Japan,China even or some South Indian states
So that tells you something
Also, the disgust at out of group behaviour goes back looooongggg, the theory is to the ice age where anyone who was a scumbag might cost the group their survival, with scarcity of resources and the need to rely on your group.
Hence you might say it's a genetic trait, engrained from millennia.
What is south Asia other than the amalgamation and tapestry of everyone who has passed the through and settled their tribe.
Scandinavia replicated can only ever be a north star that's seen in the distance for south Asia.
South Asia needs a different solution.