The white working class aren’t leaving, they are just ghettoised. The same problems we see among inner city blacks in the USA is seen among underclass whites. This shows it isn’t a race thing.
Tge root cause is welfare excess and tye deterioration of religion.
Nearly all the underclass whites have no religion. They head to church for weddings and funerals that is it. Their lives are filled with waiting for Friday and Saturday nights to get blind drunk and gagging in the gutters.
The pakis look on them as godless and only worth exploiting. They have sex at 13 and drink earlier. So the Pakis see them as white thrash
I spent a month in England a few years back and saw what you describe. I was not prepared to see 15 and 16 year old white children blind drunk and out on the street.
Society seemed officially athiest except in the case of being anti-Catholic.