At NHL level the decline it's widely exaggerated at least. Heck we had two players top4 in points, and it was not even Zetterberg, Alfredsson or anyone of our most recent recent big guns. At D after Lidstrom we have Enström, Edler, Kronwall, Karlsson and maybe a few others who'll be high in defensive scoring most seasons.
Swedes are always team players infront of anything, and that's what the playoffs are all about and why they excel. The playoffs cope more with how Swedes preferably play the game and score their goals than the regular season that has more floating and skill involved. Skill and work together is a better cup of tea for "us".
Not only those three either, Alfredsson, Karlsson, Franzen and Sedins have racked up some points and goals, Modin with a bunch etc. 16/20 Swedes have a point and 3 of those who not are playing D, and Hornqvist has only played one game.
As for your question, Zetterberg & Backstrom will be on that list, and definitely be in top of the points race if their teams go deep. Samuelsson might keep up well in the scoring dito even if I expect Sedins to be taking the driver's seat rather than him in upcoming games/series.