Continuing the discussion from Free Code tools for music-making:
Because the established terms are flawed. Aside from being an acronym, FOSS/FLOSS is meaningless in the context, making it kind of NewSpeak, which I try to avoid using. Open Source still misses the point and has been used by analogy almost to the point of meaninglessness. Free Code is a way of saying the same thing as Free Software (the original term), but is less likely to create the libre/gratis confusion that led to the use of Open Source as a way of describing the same software.
I’ve been saying Free Code for years and nobody else has picked it up, which is a shame. Now it’s a habit and I still think it mostly gets the point across. Even when it results in some confusion, it gets people thinking about the underlying issues, rather than glossing over them. Which seems like a net good to me.