I don't really agree. The problem with C++ isn't its age, it's its complexity, or what I'd call the "too many tools" problem. None of the languages you mention approach C++ in sheer breadth of complexity. For a given problem there are 100 ways to solve it in C++ and these ways of solving it may look so different from each other that it's not even apparent they are solving the same problem. Java, in particular,
doesn't have this problem: it was specifically designed to avoid this problem (read Guy Steele's interview in
Coders at Work) and while I dislike Java for other reasons, it largely succeeded in solving that problem. Python's "there should be one, and preferably only one, way to do it" is similarly trying to solve a similar issue. C's lack of features also addresses this problem.
C++11/14 gives you much better tools, but it doesn't solve the "too many tools" problem. The old tools are still there, and in fact, people are still writing C++11/14 using those tools. The result is that even if you endeavor to only use the new, good C++11/14 ways to do things, you're still going to run into issues with the old stuff and you're going to have to understand a the old stuff: and there is no end to it. Every time you make a significant change to a C++ codebase, you have to learn another dark corner of a language that hasn't had a feature removed in three decades.
Java's solution to this problem is to add features very slowly and carefully, which makes the language hard to use sometimes due to its lack of features. Python's solution is to break reverse compatibility, which makes it difficult to run older codebases. C has this problem too, but they have been more conservative with the features they have added. C# has this problem badly, but it hasn't had as much time for it to get as bad as C++.