My guess is a lot of convergence to a smaller set of known game engines. Godot, unreal, unity, plus a few others and some in-house like valves source.

I could be wrong but I presume in the past almost every game was made with its own custom engine. Now a lot of them have the “unreal engine” look.

But I’m not complaining. Looks great to me and leads to better performance and fewer bugs in the long run. Of course there are some caveats