Lol, I see Tom has learned some CGI

I think I disagree with him on this one though, especially for software. Open source software is not inherently unsustainable. Enterprise grade software making a living from support, hosting or pro features is by now a tried and true model. End user software is more tricky, donations help, especially when the project is big enough. Flathub and Elementary Store offering paid (and pay as you like) apps should help software get even more sustainable.

Open source hardware is more tricky though. Iterations are slower, there’s always an actual unit price, cheap knockoffs pop up. Prusa looks like they’ve figured it out though, and waiting to release CAD files is totally fair, to let them keep their first-to-market advantage on their new innovations

Does anybody know if Prusa accept significant code (and CAD) contributions from the community, or do they simply publish what they develop in-house?

When was it sustainable? You’re giving away your code for free, it’s going to be hard to build a business around that. And unless you can afford lawyers, or find a bunch willing to work pro-bono, these 1-man projects will keep being abused by companies that can afford to flagrantly violate these licenses.