But I am afraid I have to disagree with this being The Most Pointless Cover Ever. Madonna's "American Pie" wins hands down and I DOUBLE DARE anyone to make a viable case for anything else.
Perhaps indefensible, but I'll try:
I specifically recall sitting in a gay bar in Boston called Luxor (it now has a different name, and in fact may have changed names by this point), watching the video channel on the TVs for lack of conversation, and seeing Madge's video. I felt, much as you did, that this was utterly pointless and un-fun. But then I saw what seemed her ulterior motive: images of couples that defy traditional boundaries as she repeats -- "We started singing. We started singing."
The video's essential to the experience, but there you have it: A reminder of music's role as social, vocal protest.
Maddie bears a good witness when she wants to.