I implore you to look through https://wiki.openstreetmap.org/wiki/Automated_Edits_code_of_conduct as this changeset (among others) seems non-conformant at first glance; see particularly its **Problematic usage** section.

While there might not be an explicit prohibition on an ad-hoc addition of an easily computable tag, adding (mechanically or otherwise) trivially computable tags tends to go against OSM philosophy, and there really should be discussion before changing the last modified date of thousands of objects, as they suddenly look like they were recently verified; please see https://m.youtube.com/watch?v=ZrvcVAPdaWI at about 9 minutes in.