You're speaking past each other. You're talking about "blame" in a moralistic sense, but the other posters just mean simple causation -- "would this fault have occurred if a safer language was used?"
The former sense would be useful... if you want to sue someone or something I guess? But the latter is more useful in real life, so that's what we're discussing
I doubt the library would have reached its current adoption levels if it had been written in any other language (and I presume an other C library would've taken its place).