They aren’t rare according to the article you linked:
Although cases of lofted bounce houses get the most media attention, Knox said that just as many injuries are associated with simply jumping inside inflatables.
So for every injury jumping inside, there is one related to a lofted bounce house. A 1:1 ratio. That’s not that rare.
Knox spoke on WDUN’s Newsroom and said even a slight breeze in favorable weather conditions could be strong enough to topple a bounce house.
Honestly what you posted confirms what I have been writing.