These pages are updated manually by who is typically an engineer.
I believe theymos is the only one who handles these types of issues and if he isn’t around to deal with any problems causing downtime, he won’t be around to update any status website. Theymos also has created threads in meta advising of any downtime.
If the forum were to use one of these downtime notification websites, I would suggest statuspage.io, but the forum is really not complex enough to warrant using one IMO.
A status page would be good IMO because currently there aren't any official channels to know if the forum is facing issues other that bitcointalk itself. There is a twitter account but it's very sparsely updated. It wouldn't matter if it's manually updated, so long as it's accessible and functional when other components of the site aren't.
It can also have some functions updated programmatically that would turn red if for example the DNS was unaccesible, or clouldflare was slow etc...