One thing that's not a valid reason is the one that the author gave. "Hur dur I develop web apps and I've never heard of XSS" isn't excusable. You have to know about this stuff, even if it's not your expertise.
One thing that's not a valid reason is the one that the author gave. "Hur dur I develop web apps and I've never heard of XSS" isn't excusable. You have to know about this stuff, even if it's not your expertise.
The OWASP Top 10 is fashion, really, nothing much more.
Also there's a legitimate case for vulns that exist so far outside of your stack that you never run into them. It would be surprising, but not actually dangerous, if a pure Java developer wasn't familiar with buffer overflows, heap spraying, ASLR, etc. Same for most application-level developers and hardware-level issues like Spectre. But I maintain that the author's example of XSS for a web developer is way unreasonable.
The fact that there may be other vulnerabilities that are just as dangerous doesn't mean it's equally bad to have vulnerabilities like that, if they require more time and sophistication to exploit. E.g. you shouldn't have string comparison timing vulnerabilities in your code, but having them is less bad than a SQL injection attack even if they can both lead to the same result.