I monitor commits, rarely check JIRA, follow and sometimes answer mails and close to never develop code for that component anymore - maybe once or twice a year when I go through JIRAs.
Now what? I appreciate the initiative but don't see this working too well for me. If this was all just one repo and dormant was just a "not actively developed" flag this would be a little easier. Even better if there was a script that regularly checks different conditions and updates the flag on the website accordingly. cheers, Torsten