Well we know both trademark and copyright can be “abandoned”, IIRC, which is why Xerox wants you to say you’re making a Photocopy, and you need a facial tissue, not a Kleenex. And while I don’t disagree with your point, I would think corporate intellectual rights would be effected even more so.
Since I don’t really know the details of this specific case, the next part isn’t about it specifically per se - but flags in general.
I just have kind of an issue with the idea of an “ownership” of a flag like that. Now not talking about a flag that is purely decorative with like a lady bug or what have you. But flags such as this are supposed to represent a people or a culture or a nation or a cause. It’s a symbol. The problem with symbols is that it is really hard to claim complete ownership and meaning, as society will take your symbol and rearrange it.
So like I can totally see why this guy would be pissed that this Reclaim Australia would use this flag. I am sure the Navajo were dismayed at the Nazis using the Swastika. Or who knew the Gadsden flag would be resurrected by the Tea Party? Or the re-purposing of Thor’s hammer? Or poor, poor Pepe the frog? (Though that one is a bit different, as it was a repurposed unrelated artwork.)
Or let’s just take the American flag. Where it is flying and WHO is flying it can illicit different emotions and meanings. Above Perkins? Corporate Patriotism. Home town parade at 4th of July? Normal patriotism. Above a FOB in Iraq? Either a sense of home away from home, or encroaching foreigners. Over Iwa Jima? At a Klan rally? Well you get the point. Same symbol, different meanings.
So as a failed artist, I do appreciate and support protection of artists’ rights. But certain things like a flag meant to symbolize a people it seems a bit to “big” for it to belong to just one person. And like all things that become a cultural thing, it then becomes fair game to be co-opted, remixed, and perverted. YMMV. And unlike poor Pepe which was never meant to be a symbol representing anything, just a cartoon frog, the whole point of a flag is to represent something.