Isn't this the no true Scotsman fallacy? It looks like you're agreeing with the parent poster that a lot of people use a small subset of C++ to pretend that it's C with extras. If this is true, it's not a failure of all these people because they don't _really_ understand C++. It's a failure of the language designers because they have made something that nobody can agree on how to use.

How is it a failure when people just find idiomatic C++ undesirable, exactly because it's very different from C.

Basically, the best C++ feature by a very long mile is that it can in fact be used as an extension of C. That's what made it popular in the first place and that's still "what people want".

If it's a failure, then it's that of the C++ committee evolving the language in an echo chamber.