I note that the case is seen by commenters here as “epic” but I should like to know why. Is it because copyright protection endures for decades longer than the patent term?

What springs to mind is the 1960’s UK Supreme Court case in which a car manufacturer (British Leyland) went to law to stop after-market makers of replacement exhaust pipes. They were said to be infringing the copyright in the engineering drawings of the exhaust pipes. Is it right that the patent owner can enjoy such protection after the patent has expired? If it is right that copyright should last longer, why not also for engineering drawings of exhaust pipe systems and components?

Since then, and informed by the issues debated in that Supreme Court case, Europe has reformed its design patent law, with a maximum term of 25 years for Registered Designs and a term of protection for unregistered designs that is less than the 20 year patent term. What will SCOTUS do here? Epic!