Easy, it's better than all of them!
If you're a C++ developer on Windows then I encourage you to simply try it. I run a 32c/64t threadripper so I also don't particularly care about hardware resources. My experience on a custom C++ codebase and Unreal Engine codebase is that 10x is faster and more reliable than VS Code, Visual Studio, and Rider. I haven't tried CLion as Rider is the JetBrains tool for UE.
I agree lack of support for other languages is a bummer. I'm hoping support will be added if the tool takes off. Maybe he ads LSP support, I dunno.
> parsing C++ properly is really hard
I'm genuinely blown away he wrote a custom parser that works. Unreal Engine is big and nasty and full of a kajillion macros. My experience thus far is that 10x handles it like a champ. Better than Visual Studio. And equal or better than Rider. Super super impressive.