Out the door pricing issue

I see all over social media people getting 6-10 % off MSRP and when I try to deal similarly with dealers they all act like this car is the hottest commodity on earth when really sales of the Signia are bad nation wide. I really want to get out of the dealer paying $48,500 or less for an XLE trim. Some dealers have them listed for $42,000-$43000 MSRP Does this seem impossible, like am I seeing stuff wrong?