However, if you accept that take, I see little chances of convincing management in such a company to switch to a new, fledgling language - even if it were much safer to use. If anything, your hopes might be that you can teach their teams to use modern C++ and accordingly and slowly massage their code-bases into a more up-to-date state...
Ie., (not the least due to those vast code-bases) C++ (and Java) is (are) quite certainly going to stick around for the foreseeable future, like it or not. I don't really see any great migrations coming our way as long as those languages keep updating themselves to reflect the more significant insights from programming language research, even if those updates lag behind by years.
Just to show how bad it is to move those big enterprise ships, only now in 2017 has BMW moved from C to C++14, for their car platform.
https://fosdem.org/2017/schedule/event/succes_failure_autono...
However a big part of the problem, which you kind of refer to, when talking about lack of understanding between C and C++ differences is that, at least on enterprise space, many use C++ compilers for writing what is mostly C-like code.
Do you know why most MFC classes have an Afx prefix?
Microsoft created a C++ framework similar to OWL in abstraction capabilities, but the test group of early adopters said it was too high level and they just wanted a thin wrapper around Win32, hence Afx was reborn as MFC. [0]
I like modern C++ very much, and it is true that many of the "modern C++" concepts were already available on C++98, the problem is getting developers to actually use it, specially old school devs when working in companies where CI builds, static analyzers or sanitizers aren't part of the culture.
Which is the situation I see most of the time across many enterprise customers.
[0] http://cs.sookmyung.ac.kr/class/00891/C++/mfc-faq/