People thinking that this isn't the case everywhere need a reality check. Most software is riddled with obvious security issues. If we can remediate them with AI, great, but don't be thinking that this is something that we could only have dealt with with AI. Enough attention and prioritization of these issues would also have sorted it.
Ask yourself if we weren't currently in an era of AI-focus and AI was just another boring tool, if we would be bothering to do this sort of thing. Loads of us still aren't bothering with basic static analysis.