I think their statement amounts to something like in line of: subset of modern C++ and feature usage patterns can be reasonably safe and I am ok with it. Nothing is ever really safe of course. One should consider trade offs of quality / safety vs costs and make their own conclusion on where to lean more and where enough is enough.
There's an argument to be made that you can write safe C++ by using the right subset of the modern language. It might even be a decent argument. But that's not the argument that was made here. They mentioned two things that have only the most tangential connection to security and that aren't even part of C++, plus one C++ feature that solves exactly one problem.
