I've been admining Debian boxes for more than a decade so I'm aware of the drawbacks of its policies. That's why my desktop tracks unstable. But for a sysadmin, freezing everything for long periods of time makes for an enormous reduction in churn-related administration time. Having nothing but security updates to install until the next version comes out 2+ years later is excellent. For the exceptions, pinning can often solve the problem. And if pinning doesn't work, there's always building from source.

Like I said above, I'm new to FreeBSD so I'm not sure how much churn I'll have to endure, but I'm looking forward to finding out.

Where that approach fails is that as a sysadmin one of the responsibilities is to provide good tools to the user, not reduce work for the sysadmin. The user might be a SaaS platform, developers or more traditional (l)users. Regardless, you want your platform to be stable and efficient from a user perspective. Tracking a "Security" branch only give you one of those in many cases.

It's an apples to oranges in some regards because FreeBSD OS patchsets are essentially the "Security" branch while ports is a different issue(and one the user is most likely concerned about).

I think he meant branches which are supported for an extended duration. The quarterly branches are (currently, and as far as I know this isn't going to change) supported only for the quarter in question.