You can get a rough overview of the changes per minute looking at https://codepen.io/Krinkle/full/BwEKgW which listens to the event stream. (scroll to the bottom of the page, its seems slightly broken right now)
This shows ~300 edits per minute on en.wikipedia (5 a second) right now.
~1500 edits per minuites on all sites (25 a second)