It sounds like the rule is quite recent. You should see the active user % go down with time as your active userbase has a chance to go to your platform using their other devices. Let me know if you need further help.
Below points may help you troubleshoot the newer rule:
When was the newer profile merge rule/cross-device data source created? (It looks like it is pretty recent as the numbers seem very low compared to your other rule; and in which case, the active users wouldn't have had a chance to use other devices).
Profile merge rules- are both the rules similarly configured?
ID sync - Has the id sync for email id been correctly configured?
One more question. I have more than 1 authenticated profile option. Userid and Emailid. Userid is an older id which is showing a large number of cross device customers and small amount of active customers. This is normal because this helps me realized a match rate.
However, I have created a new id called Emailid. The logic is similar to Userid however, it captures a larger net of authenticated users. The issue is that I am getting a 98% match rate. Is this because something is not implemented correct or is this a limitation of AAM where only 1 id is able to show full net of cross device users.