I suspect that the writer of this article has never darkened the door of a kitchen to bake but remembers a parent or grandparent using "healthy" margarine in the 1970s and 1980s.
I think that the higher butter prices are another consequence of the difficulties in the dairy industry. I did buy a pound of butter at a reasonable price in November, since I use small amounts of it in some recipes.
Also, flour did still go on sale this holiday season, and some good prices were to be had by the careful shopper.