> The US is unique in taxing worldwide income [..] based on citizenship
This is technically correct, but many other countries use a similar principle called the worldwide income principle, in which all your income, no matter where it is being earned, is taxable in the country they originate in / spend most of their time in (rules vary widely, I am not a tax lawyer).
You're mixing wildly different things. Regardless of where you come from, if you live in France you pay taxes in France on revenues obtained (even if they didn't originate from France). If you're a French citizen living in Canada, the French tax authority doesn't care about you.
There are a few extremely rare exceptions to that, most notably the US, which wants to tax US citizens on any income generated, regardless of where they live and where the income is from. So a US citizen living in France getting paid from a French company has to pay taxes to France (due to living there) and the US (due to being a US citizen). There are tax treaties so the taxes paid to France would be deducted from what is owed to the US.
World income principle works the same, only it thethers you based on main area of presence, not nationality.
A Turkish citizen mostly living in Germany (-> Steuerinländer), but working in France for a French company will pay German and French income taxes (and may get the French taxes back from Germany after handing in his tax forms next year).
It's the same thing, only that nationality does not matter, residence does.
This is technically correct, but many other countries use a similar principle called the worldwide income principle, in which all your income, no matter where it is being earned, is taxable in the country they originate in / spend most of their time in (rules vary widely, I am not a tax lawyer).