Once that is said, it should be possible to work in a general-purpose open source 2d printer. The open community has achieved bigger goals. The biggest problem I can see is the entry barrier: to get a very basic printer, you have to invest thousands of time with a lot of knowledge in different areas, when a basic printer, even from the large companies, is not very expensive.
I think that one of the only chances we have for that to happen is that a company frees its designs and patents and community starts working from there.
It'd probably be easier to make a nice block alphabet for a plotter and then just print your documents as biro drawings.
But again, feeding paper seems like a very fiddly problem.
IBM must have had this use in mind because they actually made a variation of the Selectric design that could be used as a serial terminal. We have one in storage at work but I think the mechanism is seized. Wikipedia has a surprisingly long section about modifying the Selectric to work as a computer terminal[1].
[1] https://en.wikipedia.org/wiki/IBM_Selectric_typewriter#Use_a...