(One odd example is the five Olympic rings, which represent the "five inhabited continents": Asia, Europe, Africa, Australia, and the Americas.)
And the ring represents Oceania and not Australia, and this makes Australia an island in Oceania.
The whole probelm here is that the English word "continent" actually means two different but closely related things, namely the older cultural-geographical concept "part of the world" (cf Ger. "Erdteil", lit. "part of the Earth") on the one hand, and the more narrowly geological idea of continental shelves &c. "Hello, so which part of the world are you from?" is a much older question than the idea of tectonic plates, so Europe and Asia being different things has been thoroughly cemented into the public conciousness although geologically, they're one and the same. Contrariwise, the Americas both got the same name even though they're (apparently, AFAIK) actually two different things. So, it would help immensely to keep these two different categorisations separate. "Erdteil" is often called "region" in English, but that word is also already overloaded with quite enough meanings, so this usage probably doesn't exactly bring any increased clarity on the whole.
Unfortunately, contemporary colloquial English uses the word "continent" for both concepts, so confusion like yours is only all too common. To come back to your specific points:
* The ring represents Oceania and not Australia
In modern politically correct parlance it represents a part of the world ("Erdteil"), not a single geological entity. Saying it represents only the actual continent of Australia would leave New Zealanders and Micronesians without any representation at all, so that would be rather un-PC. My guess is that back when the rings symbol was adopted, PC details like this just weren't on the agenda, so they simply said "Australia".
* and this makes Australia an island in Oceania.
No it doesn't. It makes Australia a geological-continent in the region-of-the-world Oceania; or, if you will: It makes Australia a continent-1 in continent-2 Oceania. (See how using the same word for different things kinda sucks?)
It's America. It's a continent. It was named after Amerigo Vespucci.
The fact that English speakers, led by the citizens of the United States of America, in practice claim the name America for themselves and want to push the point of North and South (never quite agreeing what north is depending on the political point being made), doesn't mean that there's objective validity to it. Just a egocentric convenience and the superpower influence.
I'm specific and right, but in the wrong place (HN is Reddit nowadays, preach to the choir or downvotes).
It's not preferred. It's historically accurate and I'm not the one with the burden of proof. He asserted the wrong thing, but that didn't make you question him.
https://news.ycombinator.com/context?id=35569350
This is so funny (and trivial). It really shows how people in this site and in most of these Reddit like forums operate nowadays.
Hegemonic views can't be challenged and are the default and logic will not be used.
This is completely wrong, unless your argument is something like there being only two continents. Which is fine but pretty far from how continents are normally defined and you should probably use a different word.
By far the most egregious continent border is Europe vs. Asia, and Africa is connected to those two just as much as the Americas are connected.
> never quite agreeing what north is depending on the political point being made
You get the same political fussiness around every continent border. But the geographic boundary is pretty well decided to be Panama.
And I don't know what your point is about central america. Nobody calls central america a continent.
> En realidad no existe una única forma de fijar el número de continentes y depende de cada área cultural determinar si dos grandes masas de tierra unidas forman uno o dos continentes, y en concreto, decidir los límites entre Europa y Asia (Eurasia) por una parte y América del Norte y América del Sur (América) por otra.
It's just a great exercise of how these sites work. And that goes for more consequential stuff than this.
Isn't that the point though? North America is not an island. Asia is not an island. If NA and SA were one, they would be an island, but they are not.
If the point is Australia is a continent and hence not an island fine. But it's not because Americas will then become island because Americas is not a continent.