The functional tests were re-enabled on macOS in #18778. However it looks like they are still suffering from intermittent failures. i.e: https://travis-ci.org/github/bitcoin/bitcoin/jobs/680353191#L3136. The OSError: [Errno 41] Protocol wrong type for socket error in feature_assumevalid looks like the same one that was reported in #17240 when the tests were first disabled.