This is a lot to do with 'white' and latent imperialist 'guilt' in relation to what European nations did to the subcontinent in the past when the British Empire dominated the world. Namely the British along with the Dutch and the French etc. After which there has been much back peddling as these nations have attempted to continuously purge themselves from their sense of guilt over colonialism: theft of resources & labour from the less industrialised/poorer nations which have historically assisted Europe in developing it's economic superiority.
It needs to be seen within this context. So over time wealthier 'white' European nations are expected to embrace other cultures, minorities and refugees, whilst not ever really openly celebrating their own, (not flying their own flags, which in Britain is now seen as a sign of being racist) - as they historically have been the 'oppressor' countries if you like. And everything else has fed from this and we get where we are today. Germany is also always trying to compensate for the rise of Hitler, fascism and the holocaust, so that it seeks to be seen to bend over backwards to take refugees to it's bosom too. Regardless of what the indigenous population wants. They are never really asked. And any debates on immigration are relegated to being 'racist' even though there are rational and logical reasons for concern.
On top of which, we have witnessed years of Western military backed operations in the Middle East, which have entailed illegally bombing sovereign nations, (Iraq, Libya, Syria) creating utter chaos, whilst killing and displacing vulnerable civilians who then flee these war torn countries and head towards Europe. So our leaders create the problems, the military industrial machine creates these problems. The US is also complicit.
The final backlash of which includes a rise of the political right as working class people in Europe are left having to deal with the fallout. These people feel ignored, left behind, feel economically vulnerable, (immigration certainly drives down wages) and are worried about an ever increasing culturally shifting landscape, especially in urban areas, not so much in rural ones. Although the true root causes of 'austerity' is much more to do with neoliberalism than it is to do with immigration. It's also true that the globalists have certainly eagerly championed a free moving borderless workforce, so they can extract cheap labour. The more local working class populations always having to bare the brunt of that when competing for jobs.
But it's also interesting to note that quite a lot of non-white British people voted for Brexit and want a halt or at least stricter limits on immigration too. The subject of immigration and national identity, is much more complex than what the mainstream media would have us believe.