I don’t think there is any ‘Benefit’ of using C++ over Blueprints. That’s not to say you shouldn’t use one over the other. I think maybe the word ‘Benefit’ is probably over simplifying which you should use.
IMO, the key is to use the ‘best’ system for what you are trying to achieve. For lower level systems I use C++ because I find it far simpler to implement what i’m trying to achieve, and then expose this to the Blueprints system… but for higher gameplay type things, I prefer to use Blueprints solely, i.e If I need to open a door or animate a simple mesh etc. That’s not to say these too couldn’t be done in C++, i just find the ‘game designer’ type interactions simpler to keep within the editor.