It’s not strictly absolute (I still use and even occasionally buy proprietary software) but yes, generally speaking, I either only work for companies that release free software, or strongly advocate for my clients to build and release only free software. I’ve convinced (or been part of the process that convinced) several projects to release free software that otherwise would not, including some famous ones that have been on the frontpage of HN recently.
I am personally responsible for at least 3-4 startups never making/releasing anything but open source stuff. I advocate for the basic idea of software freedom in all contexts.
Usually “business guys” try to interfere, but it’s almost always from the misguided idea that the code is somehow valuable. People get this weird idea that their source is worth money (it never is). Most companies are valuable because of their ability to execute, not their code (which is rarely reusable outside their org anyway, and even if it is, not in their market).
Think about it: if your code were valuable, how is it that a few people were able to make it from scratch in a few months? It’s
obviously your staff who are valuable, not the code (which someone else could also make from
scratch for low cost if they needed to, just like you did).
It’s the same misguided emotion that makes people think startup ideas are inherently valuable. It’s the ability to execute, not your so-called “intellectual property” that is where the value is.