Integration is far more difficult with high immigration levels happening primarily due to economic purposes - immigrants move into ethnic enclaves where they don't have to integrate, mainly because the primary driver of migration and immigration now is money. It used to be freedom and culture which also drove the desire to integrate. Now it is ONLY money, with ethnic enclaves big enough to prevent any integration and moderation by many who reject western values while embracing the social benefits based on those values.

The added downside is that immigrants are doing worse and worse economically as higher immigration levels create more competition and a labour oversupply which drives down everyone's wages. They are disillusioned quickly.

The real problem for integration is high immigration levels: lower immigration levels and most of the problems fix themselves.