Having watched every important western of both types I canāt agree.
I think itās the other way round, the plot is not typical Spag, but the directing is.
Antoniniās similar The Tramplers is both, a simple US clone in style and story, and is the more coherent film. But also the less interesting one cause it has nothing to offer in both departments. I crudeli is more fun to watch for the Corbucci factor, but as I said as a whole also not really interesting for me. (Itās a āDean Frisbeeā film. )
The typical average western is that kind of film, and some great US westerns too (like the westerns s by De Mille or the ones with Erroll Flynn), but there are enough US westerns before the 60s which are neither simplistic nor basic. And even many more of the 60s, if we remember that the Hays code was still at work until 1967, if that is the year you are talking about.