I understand and share much of your sentiment. However, the Schooner "America", which I believe the cup was named after, was the pinnacle of yacht design back in the mid 1800s. Basically, it was the current high-tech sailboat of the day. The same could be said for the J-Class in the 20's. The 12 meters were state of the art when they became the class the cup used later (I don't recall when).
My point is that while these foil multihulls bear no relation to the sailboats that I sailed and raced, they are some of the fastest sailboats around using our current technology. Time change. Was the change from canvas to Dacron a step to far? What about the current high-tech sail materials. Modern gps, wind speed indicators, weather forecasting and computer plotting are a normal art of modern "traditional" yacht racing. What happened to the helmsman touch, ability to read the water, feel the wind shift on your cheek and eyeball that weather mark to see when you can make it?