I take your point about the age of some of these projects (though it's not like there weren't any "more appropriate" languages around when most of them started). And I'll also admit to agreeing with the idea that choice of language is nearly always a sociological matter before it's a technical one.

But I'm not really arguing that C is the best choice for large projects. I'm just pointing out the fact that many, many people just completely ignore that advice. They are ignoring that advice today -- right now. With new projects. And they've "seen that thread before" too. It's not just legacy, or lack of awareness, or whatever.

Maybe it comes down to what the "very good" reason actually is. Because given the amount of C hacking going on, I wonder if the "good reasons" we hear about nearly every day on HN aren't the most important ones for the quite vast number of people merrily hacking away in a language that is now decades old.

Knowing how some big software systems lived through more than a decade each, I'd claim that the less they used C++ and the more used C++ compilers to write a C-like code they were better. The worst parts of the project were exactly those that used the "cool" C++ features.

C is much better for really long-lived projects than C++ is. C++ is a maintenance nightmare in comparison.

Linux kernel is also a good and famous big long-lived project which I claim would have never even survived had it been written in C++. Linus seems to have believed the same.