Has this happened to your environment yet? Turning on a Flow, triggers the workflow to run on all items on your list?
We have built a few new Flow or Power Automate workflows for a new SharePoint site. The workflows are supposed to trigger when a new item is created or when an existing item is modified. We temporarily disabled or turned the workflow off to migrate content. Several hours after the migration is completed, we went to enable or turn the workflow back on. Next thing we noticed was that our outlook inbox was inundated with hundreds of email notifications from the workflows.
This is the second time, this issue has occurred. Other times, no issues when the workflows are turned off then back on. Microsoft support has no idea why or how this has happened. One reason that support gave me was that the items were cached on my browser. I call that BS.