I think the notion of a “public utility” in the sense of “common carrier” may be more important in common law than in the Nordic tradition. If Postnord had been a government agency, results may have been different.

But, and this is important, a mail carrier is not allowed to discriminate freely under Swedish law either. Labour conflicts are an exception (in many areas of law) simply because almost no one wants the government to intervene. Collective bargaining with some conflict to get the Elons of the world to play along is simply working out better.