if you put any of your "tag" URLs into this site-
http://httpstatus.io - it confirms a 404 is being returned. It isn't 403 because by default the mod sends 403 for "No Permission" errors only and 404 for all others.
The dates on the image are all several or more days ago so I assume you won't see any more past today assuming the mod remains active.
However it is pretty clear you should add your entire /tags/ path to your robots.txt file, that would be the right way to prevent the crawl issues.