I've hiked both; the Dike many times in all seasons; Huntington ravine trail only once, many years ago.
They are quite different. Huntington trail is a hike, steep in a couple spots and sometimes slick, but my buddy and I hiked down it easily with heavy packs, and never had to use our hands. Much of the Dike is like that also. But the "crux" section is definitely a vertical rock climb for about 30 feet. Climbers variably consider it Class 3 or Class 4.
If you know the Dike crux well, it's quite easy and secure, even when it's wet. But part of that is perception. If you view it as a hike, it's a really difficult, dangerous hike. If you view it as a rock climb, it's quite easy.