On the main Sci-Fi site is this link:
which goes (correctly) to the Science Fiction & Fantasy Blog.
At the bottom of this (meta) page the link is:
which goes to the Stack Overflow blog.
Looks like the link on this page a bug.
The official-looking links in the footer were never intended to point off-site; that worked briefly for a short time on the main site because it was still pointing to the old Blog Overflow site, which was redirecting to the off-site blog...
The redirect still exists, but the footer no longer links to it, on the main site or on meta.
As a general rule, we're not going to send folks off-site via an official-looking link unless there's an amusing 10-hour YouTube video on the other end.
The footer is kind of a lousy way to promote the blog anyway. I'm not entirely sure why there's even a link to the system blog in the footer, although perhaps it helps with SEO in some way; most of the links there are far more utilitarian - the equivalent of the fine print on the inside cover of a magazine: great when you want to know where to send angry letters to the editor, but not where you go looking for articles.
I prefer the way Worldbuilding does it: a meta post corresponding to the latest post, with an event that announces it on the sidebar for some length of time. That gives y'all complete control over how long each post is promoted, while giving readers some context before they end up off site (and a convenient way to post feedback if there's a problem). See: How can we improve blog promotion?