Printers are very expensive to design, especially if you care about reliably not jamming.
Printers are kind of expensive to manufacture.
Ink is extremely cheap to manufacture.
The printer industry charges a ton for ink and uses the enormous profits from charging for ink to cover the cost of design, and to heavily subsidize the price of printers.
Competing with printer companies as a startup looks like this: you burn a bunch of VC money to get a working design, then you burn even more VC money to make and sell printers at a steep loss, and once you have established a market presence your investors look on in horror as you use it to sell a very cheap commodity product a few milliliters at a time.