> So basically...

Well, not really.

Consider lambdas in C++ (that was the perspective of the post I replied to). Before lambdas, you used functors to do the same thing. However, the syntax was slightly cumbersome and C++ has the design philosophy to add specialized features to optimize specialized cases, so they added lambdas, essentially as syntactic sugar over functors.

In zig the syntax to use an anonymous struct like a functor and/or lambda is pretty simple and the language has the philosophy to keep the language small.

Thus, no need for lambdas. There's no re-inventing anything, just using the language as it designed to be used.