If you actively try to avoid software that is licensed under BSD or ISC, only Gnu's Marxist license, then that means you won't use OpenSSH or the security tools ported over from OpenBSD into both Linux and Android and will not use an operating system or programs that have been compiled with LLVM/Clang.
I prioritize system security, and for that I only care about open source and reject free/libre software due to all of its built-in political implications. But also defend the right for people to make proprietary software. I won't use it, but defend people's right to make it.
People must give up how they want the world to operate and deal with what is. For example, FSF is wholly incompatible with BSD and the 2 distinct cultures and views can never work together. They are both open source, but that's where the commonality ends.