I agree with you and would love more "real world" things to be open source. I do like the ethos within software/tech that things are open-sourced often. It doesn't exist to nearly the same degree in many other "physical world" type industries.

I think government/ bureaucracy moves slowly and most people working within them don't come from a software background so a lot of the older norms of not sharing things (outside of things like data/documents) is just the way things are done. I expect to a lot of these people sharing a source code is treated exactly the same as sharing any other mechanical designs which they just often don't do.

Hopefully both things will change.