The person 'bragging' was not a countercultural user, but rather the FreeBSD engineering lead. They were, however, talking about FreeBSD's response to security vulnerabilities, in contrast to Linux's response.

> thus not immune from the types of bugs that stem from that lineage

They never claimed that FreeBSD didn't have vulnerabilities. I honestly have no idea why grandparent decided to bring up their comment when it exactly validates what the person they were criticising says. GP admits the response to the vulnerability was well-coordinated. The response to security vulnerabilities was the exact, and only, subject of the post they're calling out.