[sylvainkalache]

In my experience as a former SRE currently working for an incident management SaaS (Rootly).

Two main reasons: 1) The status page update is not automated. It takes time for the incident management process to go through all the steps and updating the status page is generally not the first one. It's often an overlooked one.

2) The company would rather not communicate that they are/were down, or they are not yet sure of the impact, and therefore don't yet have the correct information to share.

Of course, all modern incident platforms will offer tools to update your page super easily/in real-time. But tooling is generally not the main issue; it's process/information.