The blueprint will be open source and you could technically build it yourself if you have the patience. They are quite proud of how few parts are actually involved in it
I respect that point of view. But to me, it being easily hackable and lacking the surveillance features of all other modern printers[0] is still a strong selling point and I hope for the project to succeed.
And that's entirely fine; it can a positive thing without being open-source. An institution can be a positive thing without being democratic. A food can be delicious without being a meat.
As much as this is nice protect, and physical one so different things any, still you cannot give/sell some software/design/media and restrict who, where and how someone can use it (noncommercial, not in this country, not at that phase of moon) while calling it open source, public domain, or similar.
As long as softwsre isn't going to be proprietary, it is a good idea just shouldn't misguide about being open source.
> Open Printer will use the Creative Commons BY-NC-SA 4.0 license for all of its files, including electronics and mechanical design files, firmware code, and the bill of materials.
Are you miffed by the restriction on you selling derivative open printers?