A interesting study in historical trivia would be to find out why the chemical known as “lye” (lute, pa Norsk) came to be associated with the restoration to an edible condition Atlantic codfish that has been gutted, dried (by exposure to the sun (Yes, Old Sol), in times past, then restored to an edible condition by soaking in water to eliminate the lye (sodium/potassium hydroxide, I believe it to be, primarily) and the very practical reasons for thusly managing huge amounts of codfish in order that Norse folk (a few of them my ancestors) might survive the winter season. With modern mechanical refrigeration the use of lye for preservation no longer really applies.
Ergo, I surmise that what is today marketed as lutefisk is codfish that have been gutted, washed and as quickly as practicable preserved entirely by means of modern, electrically powered refrigeration.
Why didn’t they salt it instead?