Its immature to suggest rewriting backend of some bank written in COBOL half a century ago, because Go lang is so much better. That would be a suicide.
No sane person will propose to use COBOL for brand new project.
Again my point is that bashing - modern, in use - languages is stupid thing to do. Current languages are used for a reason. Speed, convenience, libs, support etc.
Going back to C++ vs C. Have a look at Linux kernel written in C++.
Languages are tools, and each tool has its purpose and should be chosen for a purpose.