The thing about Go interfaces (and C++20 Concepts) is that you can name a type that contains certain methods or behaves a certain way, but you don't actually have to inherit from the interface or concept explicitly - anything shaped correctly that conforms to the interface or concept will work.

And at least with Go, if you try and pass something in that doesn't conform to the interface, it is very particular about telling you what you're missing. One downside of C++ templates is that if you have a problem with what you're passing in, you might get a horrendous error message somewhere deep in the implementation - or worse, your code might compile just fine, but have unexpected behavior - instead of a nice "Hey, you need to add a method named `foo` to this type."