The problem is unsolvable. In order to make C++ memory safe, the language has to be changed so much it might as well be a new one - requiring a rewrite of existing codebases.

If what we are talking about then is a completely new C++-like language, which will take a decade or more to develop, we might as well just use Rust, which is available right now and working surprisingly well.

This is exactly what Google and others have decided to do.

C++ is not going away, due to the staggering amount of existing code. But its usage will stop growing and then start to slowly shrink.