there are several, following slightly different designs [0]. entt and flecs (mix C/C++) are currently the most visible [1]. older and more established engines are getting into the game as well [2].
its just a data point that C++ has constituencies that have not given up on it yet.
But the two bigger projects don't contribute to the argument actually.
This flecs (which looks very interesting on first sight!) is a C project with C++ API bindings on top as I see it. The other one is a Godot library (which I have to examine closer as I'm specifically looking into Godot).
The collection of GitHub project looks mostly like engines. So not really games as such. (Also I'm not sure how recently those projects where started. There was no real alternative to C++ for game engines for a long time. So all older projects are likely C++. This does not prove the point that anybody would grab C++ today).
its just a data point that C++ has constituencies that have not given up on it yet.
[0] https://github.com/topics/ecs?l=c%2B%2B&o=desc&s=forks
[1] https://github.com/SanderMertens/flecs
[2] https://github.com/GodotECS