That's a good point, but on the other hand, who wrote the languages? Is it possible for a human to write a language which another human can use and create no bu

That's a good point, but on the other hand, who wrote the languages? Is it possible for a human to write a language which another human can use and create no bugs? In either case - unsafe language and safe implementation, safe language and unsafe implementation - there is the possibility for bugs, and definitely security ones. Just because you can't cause integer overflow doesn't mean you can't exfiltrate petabytes of data. I think the major security consideration should be a comprehensive review of the entire system. Regardless of the language or implementation, a regular architectural and non-functional review of all the components in a systematic way is going to provide more security gains than any other single thing. Maybe we should be focusing less on the tools we use and more on improving that workflow.