The classic counterexample is GCC, which so contorted its design to prevent being embedded in proprietary software, that it allowed LLVM to take off as a powerful competitor not only due to its friendly license but also by virtue of being architected in a way easier to integrate with IDE software. Stallman’s own self‐own.

Different purpose, which succeeded. It is a different philosophy to not be jealous of whatever use someone may make of it, even to making money. Why force a commercial venture to duplicate work if you can help them as well? If you can release high quality software which gets used and advances the state of the art _everywhere_, then that sounds like a good deal. I understand why copyleft might be useful in some circumstances, Linux has gained great adoption with the commercial tech giants because of it, but there is room for all philosophies in the code world; and they suit different purposes and temperaments. Some people simply feel happy that their high quality code is adopted and used, maybe they play Playstation and are happy they contributed to high quality entertainment, the world is a better place because of it.