I don't think it has more authority or correctness. That's part of the joke. I've actually read various incarnations of this argument on the internet (mostly carried out on Reddit), and at this point I consider it to be somewhat of a meme. What I remember from all of the times I've seen it brought up is that some international standards committee declared and it to be "aluminium" and so some internet denizens (especially Europeans who already tend to pronounce it that way) proudly declare this to be the authoritative be-all-end-all resolution to the subject, whereas the other side (typically those speaking American English) remind everyone that the person who made the original discovery considers "aluminum" to be correct.
Why I am grouping "gif", "png", and "alumin[i]um" together here is that people consider some nebulous authority to be the prescriber of all things pronunciation. I personally think that pronunciation is derived from how it is commonly spoken, and not the other way around. Hence its inclusion in my playful ribbing. If I appeal to the correct authority, can I make them change their pronunciation? Maybe it wasn't very funny.
Ah, got it. I thought that the joke was that you were tricking them into using a less favorable pronunciation on the basis of some perceived authority, rather than the joke being that there would be such an authority at all.
Why I am grouping "gif", "png", and "alumin[i]um" together here is that people consider some nebulous authority to be the prescriber of all things pronunciation. I personally think that pronunciation is derived from how it is commonly spoken, and not the other way around. Hence its inclusion in my playful ribbing. If I appeal to the correct authority, can I make them change their pronunciation? Maybe it wasn't very funny.