I'm always shocked at the age of some really important bugs. Large optimization potentials of many public / well used / open source systems have been noted for many years.
Consider that the web has changed a lot over the past 14 years. Back when this bug was filed, it was much less common to have many tabs open, and those tabs would have contained many fewer documents on average. So even if ABP had existed back then, the optimization potential would have been much smaller.
