Expand beyond C/C++. I realized about halfway through my career that full time C/C++ work was diminishing and higher-level languages and frameworks were going to open up more jobs (they did). For me, this involved learning more web tech (python, javascript, UI dev) as well as Java. As a C++ dev you might want to also look into Rust as thats becoming more prevalent and popular these days.
Hell, you should just apply to a bunch of Rust jobs, noting your deep experience in C/C++, and see if they bite.
Good luck.