You mention in that article that $29 is too high. But would you really need a status page for a service unless it was generating enough revenue to justify $29? A status page seems like a "oh now I have a critical mass of customers and need a way of sharing uptime" vs being something you need pre revenue or early revenue.
I believe so. At my workplace we use Cachet for our internal tools and applications - we wouldn't want to pay $29 a month for something internal like that.
There are a lot of people using Cachet in the same way as we do and even for services or business that are making money.