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.
There isn't much return or expertise on building an open source 2D printer, as opposed to 3D printers.