Whether or not it works in Denmark is a separate issue. But let’s pretend that it does work in Denmark. Denmark is a very small (<6M people), quite homogenous (88% Danish origin) society. The US is as different from that as can be. There is no reason to believe that a system that works in Denmark can be transplanted to the US and work. To state it bluntly: Newark, Baltimore, St Louis, etc ain’t gon’ be playing nice.
Socialism can be made to work in small homogeneous nations where all, or almost all, regard themselves as members of a large extended family.
That’s not the USA.