"Let's examine that claim. Sweden is doing great, Denmark almost as great. Norway has the oil (and a *lot* of it) and has had the god foresight to save oil money from the good times to insulate against poorer times. Norway is doing exceptionally great. Which leaves Finland. Sure, Finland has challenges which can be attributed to a disrupted monoculture. But they are not dismantling the welfare state by any means. They're innovating. None of the Nordic countries are about to "drop" like a fly."
Sweden is not doing great. Most of their GDP increase is fueled by migration related activities and financed by borrowed money.
Norway is not doing exceptionally great, not even great. We did well when the oil price was above 100 USD/barrel. Now, with an oil price around 35 USD/barrel, Norway is in deep shit. Both countries have huge unemployment rates, partially camoflaged and hidden.
Sweden's and Norway's economies are mostly fueled by one thing these days: Migration. Migration keeps demand for housing high and hence housing costs high, allowing the middle class to finance their consumption by borrowing on their property. Migration also generates lots of activities, inflating the GDP.
Remove migration and the property market will collapse. GDP will also shrink. Basically, the nordic welfare states are pyramid schemes.