Sadly only applies to these high end ones; I got a cheap Epson one and found out after moving it to another country, that the cartridges are indeed vendor+region locked.
EcoTank printers don't use cartridges. You fill the ink tanks with ink bottles. They've come down in price, you can buy an EcoTank printer for ~$229. A couple of other companies have followed Epson in offering these kinds of printers. Sadly Brothers' version requires a proprietary cartridge tank.
I looked it up and you are 100% correct. I now object to the existence of the term, as it clearly attempts to imply that legitimate activity is close to black market activity, but this is the correct use of the term as it exists. (Thank you for correcting me; it is far better to object to the right thing.)