As I mention upthread, a lot of the talk at the time was about overall quality of the software. So an interpretation that the total number of bugs would be reduced is well aligned with this outlook.

If the objective is just to fix bugs that have been found, well, that doesn't really feed into this narrative. Also, ESR was making a very large number of claims about the efficacy of OSS, and limiting the scope to bugs already discovered would not really align with the rest of the goings-on at the time.