I've been using the text messaging system a few months. It's been interesting to see more clearly how the buses are flowing. Finally I noticed the sign in the bus showing the system.
The system works with the Automated Vehicle Locator that buses have been delivered with for the past decade or more. Thankfully this is a low technology solution enabling people with basic phones access to the information.
I would suspect the delay in utilizing the technology simply was a matter of neglect, which would be made worse through lack of maintenance.
There are more technologies that would be very easy to implement, it takes people saying it matters. For what it's worth - I'd like internet access on the buses.