It's not about race, it's about culture and education. For instance, Chinese immigrants are usually an economic boost anywhere they go, due to the can-do attitude and respect for education and business activity in the Chinese culture in general.
Also the Chinese immigrants in question, like many others, usually immigrate seeking a better life, it's a strong self-selection filter. Middle Eastern immigrants of last 10-15 years in Europe are refugees, displaced by wars; they did not choose Denmark (or other Western European countries) because they planned to integrate and to prosper there, they ran there to merely stay alive. They need a lot of help adapting. Even if they are very willing to work, they may lack the knowledge required for gainful employment, and there are only so many dish-washing and trash-disposal jobs.
Those who adapt can make it big; consider people like Freddie Mercury or Nassim Taleb.
The sultanate of Zanzibar is technically closer to Africa than to the Arabian peninsula, it was a remnant of the Omani empire, with very thick Middle Eastern influence, and obviously Muslim culture.
The problem with immigration isn't immigrants, it's racists. Immigration has never caused me any problem at all - it's added a lot to my life and my communities, in fact - and I've lived around many immigrants.
> Chinese immigrants are usually an economic boost
Chinese immigrants were hated and discriminated against for much of US history, going back over a century. You could hardly pick a worse example for your claim.
The US is built by uneducated immigrants - including from China - who came to the land of freedom and opportunity. China was a land of extreme poverty and illiteracy for much of US history (something Western countries had a hand in causing, and I'm very glad for people there that they have so much more prosperity now).
(However, the most prosperous Chinese people are in the democratic areas, Taiwan and, until recently, Hong Kong. It's freedom and democracy, not culture and language that matter. Give people freedom and they prosper.)
It's all just stuff fabricated by racists to rationalize their prejudices. Look at the horrors Europe has inflicted on itself and the world due to these prejudices and rationalizations - the most destructive events in human history. Enough.
More racism on their part - that's the problem, as I said. I also very much doubt that is true, but generally people do generally segregate by economic means, and first generation immigrants understandably tend to live in their own communities, everywhere. Where else do you find people to talk to, who understand you; where else do you even find dinner or some decent proper tea?
Also the Chinese immigrants in question, like many others, usually immigrate seeking a better life, it's a strong self-selection filter. Middle Eastern immigrants of last 10-15 years in Europe are refugees, displaced by wars; they did not choose Denmark (or other Western European countries) because they planned to integrate and to prosper there, they ran there to merely stay alive. They need a lot of help adapting. Even if they are very willing to work, they may lack the knowledge required for gainful employment, and there are only so many dish-washing and trash-disposal jobs.
Those who adapt can make it big; consider people like Freddie Mercury or Nassim Taleb.