Nordic state ownership is working perfectly fine, which is no doubt why Stephens makes no mention of it. In fact, if his intellectual compatriots are any indicator, he would probably wave away these examples and say that the countries are really capitalistic. This is the curse of socialism in the discourse: if countries do it well, people act like it is not happening.
The different treatment of Norway and Venezuela is the best current example of this selective tendency. Venezuela’s currency and price mismanagement has stoked an economic crisis that conservatives then attribute to the fact that the country has extensive levels of state ownership owing to its nationalized extractive industries, which it calls socialism. Yet Norway has even more extensive levels of state ownership, also owing in significant part to its nationalized extractive industries, but somehow escapes the socialist designation.
For conservatives, the word “socialism” does not really refer to state or collective ownership of capital, but rather poorly-managed state or collective ownership of capital. From there, the claim that “socialism” leads to poor management becomes tautological, as every example of well-managed collective ownership is either ignored entirely or conveniently excluded from the socialist label.