C++ iirc is used mostly for microprocessor code

lol no, it's used almost everywhere where performance is important and people want(ed) OOP, from tiny projects to web browsers (Chrome, Firefox) to game engines (Unreal, CryEngine). Many of these are hugely complex and do encounter segfaults on a somewhat frequent basis.

Saying C++ is mostly used for embedded applications is like saying C# is mostly used for scripting games, i.e. it doesn't nearly cover all the use cases.

higher-level languages also exist

This depends on your definition of "higher-level", but many people would argue that C++ is on a similar level to Java or C# in terms of abstraction. The latter two do, however, have a garbage collector, which vastly simplifies memory management for the programmer(generally anyway).

I also currently use it for a new project since all needed 3rd party libraries are from a very specific domain and the project has a deadline, so writing and testing wrappers for Rust that would provide me with any meaningful advantages down the road are too costly to budget for before the deadline.

That could become part of a future refactoring, though.