At best this would be 1.7x more _discovered_ bugs. The average PR (IMO) is hardly checked. AI could have 10x as many real issues on PRs, but we're just bad at reviewing PRs.
https://www.microsoft.com/en-us/research/wp-content/uploads/...
I've seen way more human comments of "I don't know what this does but if I remove it everything breaks" in systems.