Believe this is similar to this post
Figuring out the logic for this is likely highly complicated because there are so many different types of changes a way (what OSM calls a street) could undergo. It could get new nodes, delete nodes, move nodes position, street renamed and many more types of changes. Even if a list of streets is provided in the update emails, for some the OSM changes won’t have any affect on their completion status. Ex: Two people have run & completed the same street. OSM change occurred that moved some of the nodes to align with new construction. Person 1 has GPS recordings that still keep them over the 90% node threshold so they continue to see it on their completed streets list. Person 2’s GPS recordings were a little wonky and now the new node placement sees them drop below 90% and it goes back on their incomplete list.
If changes were included in city email updates or even in CS UI, person 1 wouldn’t care cause they still have street completed. Person 2 though may be confused because they would need to know exactly what changed on the street in order to know why they now have to re-complete the street. In a big or growing city, this could turn into a lengthy email or page.
I agree it may be useful to know this information but not sure it would be super readable. Creating an overpass query would likely be a better option IMO.