Have you considered that perhaps if the idea of integration itself is considered abhorrent by a culture then that culture will very rarely be accepted anywhere?
Or to put it another way: if everywhere one goes smells like feces, maybe one should check their own boots
They want the benefits of being part of the community without being part of the community
For an example, take a look at the history of the Cagots in France, who were (are) ethnically identical to other French but due to their psychological treatment and ostracizatìon were forced into tight communities for survival.
https://en.m.wikipedia.org/wiki/Cagot
This can happen to any arbitrary group of people sufficiently singled out for any reason. A similar case exists in Japan. Then if that group remains together for fear of the abuse they receive, the broader population says "they want to be separate".
Also, your shit on boots metaphor is highly offensive, but I'm answering you as if you aren't a bigot. Sometimes the reason people end up as bigots is that no one treated them with respect and gave them complete answers.
But contrast that with, for instance, Kaifeng[0]. The biggest fear of Jewish believers is that they will encounter a society like America or China which swallows their talents whole and integrates them fully.
Put another way, it is a fear right now in segments of the Jewish community that without antisemitism, Jews would cease to exist. And there is a truth to this borne out by history. In Jewish communities it is practically taken for granted that if we had been treated equally, most of us would have given up our identity ages ago.
[0]https://en.m.wikipedia.org/wiki/Kaifeng_Jews