The discussion is not about what should be done, only about Sweden's claim that there is no problem. If they say "yes there are criminals, but only because they are poor", they are dodging the issue.
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edit: Hacker News doesn't let me post more comments. So here is the comment I wrote, but I'll probably refrain from further ones:
"poor swedes could be deported and rich immigrants could take their place"
This is already happening in a way - it is called gentrification (not replacement with rich immigrants, but in general rich people will cluster together).
But Swedes formed a "state" and endowed some people with citizenship, but also giving them responsibility for their own people. So their responsibility should be to their own people first. Of course you can argue that forming such a state is immoral, but I think there are some practical arguments in favor of it.
As history has shown, states are very well capable of deporting significant fractions of their citizens, though. But presumably atm Swedes rate the ensurance to not be deported higher than the inconvenience of living with poor people.
The gender angle: yes, that is a popular argument in Germany, "but the refugees are only criminal because they are all men". But it should be possible to take that into account statistically. And even if the higher proportion of males would be the only issue, it still wouldn't change the fact that immigrants are causing problems. After all, they have a higher proportion of males.