[groby_b]

Occam's Razor thinks you might want to go to a library and read about power law distributions.

We do have continual events. Most are extremely localized and small. Some reach the "local intervention" stage. A tiny percentage of those reaches the "newspapers elsewhere write about it stage". Occasionally, you get regional crises (SARS/MERS, for example). We finally got a global one.

And yes, there are simultaneous outbreaks. All the time. We had, during the middle of Covid, several Ebola outbreaks in Africa. There was likely a large number of avian flu events that just didn't affect people because it was lost in the noise.