Aren't most games developed with C++ or other variant? Must be a headache relearning programming over again. Like the statement says this wont be easy.
Rust was mentioned as an alternative as well.
Good game devs use C++ to avoid problems that are inherent to C# (used with Unity). One of the problems is due to the memory management technique named 'garbage collection'. In a nutshell, you don't have to manage memory manually, which is safer, but it comes at the cost of performance issues and other, more insidious potential problems. It's not entirely safe either. On the other hand, managing memory manually in C/C++ requires a lot more experience and is less safe.
Yeah, changing won't be easy. Not only it's much harder and slower to develop in Rust, but there are tons of legacy C/C++ libraries that would have to be rewritten, or it wouldn't make sense. It's the same for OSes like Windows and Linux, though Linux is tentatively embracing Rust in its kernel.
I'm not sure why the ONCD publishes that now because it's nothing new. Memory safety vulnerabilities have been fought against since Tony Hoare
introduced the null pointer in 1965-ish. Buffer overflow exploits using another flaw of those languages have been reported since
the Morris Worm in 1988. Contrary to what Grossman said, there aren't practical and mature solutions yet, but we've made good progress.
The question is: how many managers will be ready to pay more for safety when they can get the same functionality at a much lower cost? It's never been going that way.