> Every metric that matters to us has increased substantially from the rewrite, and we even identified some that were no longer relevant to us, such as number of bugs, user frustration, and maintenance cost.

That has happened more than I'd like to admit: massive overhaul effort, $new_thing is an improvement in many ways but has all of the reliability and maturity problems of a new system that hasn't gotten years of patches. But the team feels like they have to show ROI on reinventing the wheel, so they massage the metrics to look like an unambiguous success, when everyone involved at the ground level knows it wasn't.