What are the differences between @nrwl/web:webpack and webpack?

I'm starting to configure my project using Nx and webpack. I can not understand the use of Nx executers at all. What is the benefit of using @nrwl/web:webpack instead of webpack? All I understand is it's just a layer of abstraction over webpack. Are there any performance optimizations or something? Isn't it better to use webpack directly since it is simpler to configure and does not have any extra abstractions?