I’m wondering about your ‘immigrant-refugee’ dichotomy.
I seem to recall lots of ‘refugees’ from Viet Nam who have become outstanding citizens.
https://en.wikipedia.org/wiki/Fall_of_Saigon
Unlike immigrants, who choose to come here, refugees are brought in by the host country, which is then responsible for their relocation, resettlement and well-being. They can’t be deported. Immigrants can be.
The Muslim refugees happen to misuse this privilege the world over. I don’t know of any Vietnamese (or any other group) misusing this status, either.