I also have "On This Day" turned off, because it's not possible to Exempt/Omit selected folders from what it shows. Who on Earth wants old relationship photos (however nice!) from recurring and constantly reminding everyone of previous relationships? You can't even move photos into archive locations outside of the /My Pictures/ directory, because OneDrive still finds them. So the only option is to turn off On This Day, which is a shame, because I do in general like the feature. It just needs some extra settings and controls to make it suitable for real-life humans to use.
For this any many other reasons, many users HAVE found out how to turn off On This Day. The Microsoft Feedback Hub's thread on the ability to turn it off is one of the most popular ones regarding OneDrive.
So Microsoft's response is to recreate the same feature, and call it "For You". Now, "For You" regurgitates historical photos without any controls over which ones it shows. Except that there's no setting to turn off "For You". And it also... it's like an app getting angry revenge... now it also appears in the Notifications Bar as well as on the web front end for OneDrive.
The only Notification Bar settings are to "Turn Off Notifications from One Drive" - but I want the other notifications. Just not "For You" ones. Or "On This Day". Or whatever Microsoft calls this horrendously insensitive feature next year.