Alright NJ BIG pockets then if you like. I still have no problem with it and as I suggested, I also have no problem getting immersed in some of these cultures wherever possible and appropriate.
'The reality' (for me at least) is that I have made the effort to get to know people from some of these areas (eg. Indian, Turkish, Nepali, African, Sri Lankan, Polish) worked with them, learnt some of the lingo, music, cultural differences and feel enriched by the experience.
"...where “outsiders” are most definitely unwelcome"; well, I've never experienced this, having shown a little acceptance of them as people and a genuine interest in their culture
If you wish to perpetuate the highly dubious (IMO) notion that 'multi cultural Britain' is bad in some way, that's your look out.