Take a gold coin for example. You can test it's indeed made of gold without needing to know where it's from.
Same is true for good money as a general rule. Say you get a US dollar bill. What you want to know is if it's genuine, not who's been using it.
> "Imagine a world where every transaction (...) is open and transparent. No way to hide that corruption, that drug money or whatever else corporations and states are up to. No way to just make up money on the spot if you are rich and have a printer. No way to hide inequalities, at the workplace, between classes in a country."
That's just wishful thinking. Most corruption and inequalities are in plain sight, wrapped in a web of social power and blackmailing. You think the farmers will stop getting subsidies? Or military industrial complex will grind to a halt? And what if you consider that drug money is legit? Plenty of markets are legit but don't have the support of the government.
What you are talking about is not a way to remove corruption; it's a way to insure those in power will have even more power. It's also making sure the politically correct dominates everything. Better not buy something that could go against the will of the Church, because they'll know it...
No, really, traceable money is it's own kind of hell.