Apple has always been behind on new designs. It took Samsung this long to get this close on a foldable and Apple's version will most likely have a good head start on its first generation. Besides, not a lot of folks dropping $2K USD on a phone these days.
Hmm...I know this is a popular claim, but we keep forgetting that there are times when Apple's designs are ahead, and times when it's not. It's just a common view that Apple is "always behind on new designs", forgetting history -- iPhone design was innovative and new, so were thin laptops, and also with noise cancelling earbud, and so were the various iPod designs.