Having had some problems with eczema a few years ago, I did start using soap on only the smelliest parts of the body a few years back, and it helped a great deal compared to the "lather up entire body in shower every day" strategy before that. I don't know that I'd agree with "hands and nowhere else", but I do think we have too little information on our skin microbiome and how it works (or malfunctions) to say we know what we're doing in regards to soap. All of which goes double for soap with antibiotic added.