I talked a bit about this years ago: https://news.ycombinator.com/item?id=37007815
TL;DR: I'm surprised this isn't a laser printer, as those are actually quite a bit easier to design and manufacture, especially if you can use a cheap, older, commonly available, remanufacturable toner cartridge.
Inkjet cartridges often contain the print heads; toner cartridges still need a fuser roll and imaging head to do anything.
There are still quality laser printers on the market without extortion and surveillance built-in, unlike inkjets. The need for an open laser printer is less dire than for an open inkjet.