I don't think it's a matter of maintaining the purity of the meaning, it's about maintaining the intent. The point of FOSS isn't to let people benefit up to the

I don't think it's a matter of maintaining the purity of the meaning, it's about maintaining the intent. The point of FOSS isn't to let people benefit up to the point where they start being able to outcompete you, the point is to let people benefit freely. If you want to achieve the former, you can just release it for free for non-commercial purposes.