What does this have to do with anything? Everyone in the company works on 3 languages. Introducing a new language, with new runtimes and build tools and domain expertise introduces a ton of overhead.
> It will be in my experience. I haven't felt like C++ slows me down in a long time. Modern C++ and STL vectors + hash maps is the vast majority of what you need.
Every tool set has its own set of idiosyncrasies and bugs and general bs that has to be learned. Saying that introducing a new set of tools is cost free is a stupid lie.