I can’t speak to phrenology per se, but phrenology’s modern analogue is, in my opinion, the “genetics” argument. Whereas phrenology was some attempt to “explain” how the apparent shape was indicative of underlying brain structure, contemporary “scientific” racists will use genetic differences to “explain” whatever behavior they want to attribute to it.

Not necessarily phrenology specifically, but scientific racism is a thing. One example is Stefan Molyneaux, if you want someone to look up. The “science” these people use is often poor or extremely misleading.