One surprise of the recent firmware update for the Switch was the ability to use the Wii U Gamecube Adapter for it...
My bf got one a while back, and I was excited but was quickly disappointed that it was just for Smash Bros (which neither of us play, really). So the fact that this will work system-wide (and not specifically with just one game) with the Switch is exciting and illuminating - like what do they have in mind that will utilize the GC controllers?
Outside of another Smash game... haha.
In any case, I'm glad we got one back when it was $19.99... crazy, but also not surprising that it's way more expensive now.