Can you explain why that's not a good idea? I have no clue, really, but I'm guessing something about libraries.
If you're really really careful, it can work fine, and your trip will be efficient and productive. But it's really hard to do it properly -- you could hit a car (buffer overflow), you could get hit by someone (heap overflow), or your brakes might give out (input sanitization fail).
It's not that it's impossible or that it's a "bad idea", it's just that it'd be a lot safer to spend the extra resources on a motorcycle (Python) or an SUV (Rust).
And of course there are security bugs (eg, goto fail) that would affect any language.
But given they are the current mainstream options for the time of applications they are used to, better use modern C++ like you are advocating and stay as far as possible from any pure C constructs.
Additionally use static analyser, enable all warnings as errors and turn on pedantic mode.
this is not really true, you can have temporal memory safety issues using STL and boost.