That's because that is what a lot of people did in the last years [1] to pad their resumes or to force developers to backport patches to older (but supported) kernel versions that wouldn't have gone in if they didn't have a CVE attached [2]. Maintainers have been legitimately swamped with low-quality spam for a very long time. Only recently, in the last few months, AI actually got "good enough", the problem is that maintainers still have to differentiate between AI slop by wannabes and by AI-assisted reports reviewed and refined by actual human professionals.
[1] https://www.zdnet.com/article/how-fake-security-reports-are-...
[2] https://opensourcewatch.beehiiv.com/p/linux-gets-cve-securit...