The Eagles’ “Long Road Out of Eden” came out in 2007, 28 years after their last studio album, “The Long Run” and 13 years after they reunited. It is a very strong album and one of my personal favorites.
Boston’s “Third Stage” came out eight years after their second album, “Don’t Look Back,” and also received positive reviews.
John Fogerty’s album “Centerfield” came out ten years after his last solo album and is considered one of his best.
The Beach Boys released “That’s Why God Made the Radio” 16 years after their last album and it has been called a return to form.
I don’t know if any of these albums would be called masterpieces, but they certainly hold up to the artists’ prior standard of work.