Regardless of whether you're pro-patent or anti-patent, pro-Apple or anti-Apple, pro-Samsung or anti-Samsung, this was a terrible decision. It threw out 140 years of precedent, and then explicitly refuses to replace it with anything.
Specifically, up until 1885, the patent act had damages for infringement of a design patent that were "the actual damages sustained". In 1885, there was a design patent infringement case having to do with carpet designs. The lower court said the actual damages were the infringer's profits, in $ per yard of carpet sold. The Supreme Court reversed and said that since bland carpets have some intrinsic value, then the damages should be limited only to what part of the profits that were explicitly due to the design, as opposed to the carpet. I.e. if you can sell this carpet for $5/yard, or you could sell a beige carpet for $3/yard, then the profits due to the design are $2/yard.
Mmmkay, whatever, but that's not what Congress intended. So in 1887, Congress explicitly rewrote the statute to reverse the Supreme Court's ruling, saying that the damages for infringing a design patent were "the total profit made by the manufacture or sale of the article to which the design had been applied." This is how checks and balances work under our Constitution... The Supreme Court can interpret anything that's ambiguous in a statute, as a check on Congress; and Congress can draft statutes that explicitly overturn Court rulings and say "x is the proper interpretation, rather than y". Here, they said it was the total profits for the sale of the article, so that infringing carpet is back to $5/yard.
So that stood for 140 years (including the 1952 Patent Act, where Congress again said that the damages for infringement were the total profit).
But then here, the Court steps in and says "oh, by total profit, it's just the total profit for any component using the design, not the entire article." So, for example, the design on those carpets may only apply to the top fibers and not the mat into which they're woven, so the profits are... well, no one sells just the top fibers, so no one knows. And the justification for this is based on the fact that you can get a utility patent that covers a component. But that's not really a good justification to overturn 140 years of precedent and completely disregard what Congress has said, twice.
And then if that weren't bad enough, the decision ends with "so how do we determine whether the 'article' for purposes of infringement is the entire device or just a component? That would require us to set out a test for identifying the relevant article... But that's hard, so we're not going to do it."
It's as bad as the Alice Corp. decision with Justice Thomas saying, "abstract ideas are unpatentable. What's an abstract idea? Eh, we don't need to define that." Both pro-patent and anti-patent ridiculed him for that, rightly. This decision is at least as bad, with it's "we need a test to identify the relevant article, but we're going to punt on that question and hope that someone else answers it."