The issue here is likely related to business units that were acquisitions, with the breached product in question having been developed pre-acquisition by a code farm staffed by interns in some developing nation. I spent a few years trying to unfuck some of those messes and moved on.
It's more a problem with their reckless growth over the last decade than anything. (ed) Due diligence is obviously lacking, but I can personally attest that nobody in senior leadership there willfully ignores matters of security once it becomes known.