Completely covering the entire top of your foot is even worse. So itchy and sweaty. I'll take the strap between the toes any day. Only time I'll wear anything other than flip flops is because I have to for work or a formal event.
I am so confused how you are able to tell the gender of the shoes and person from that photo because I can't see anything stereotypically associated with gebnder
Near where I live is a shallow (waist deep) bay with a rocky sandy bottom: barefoot not advised. There're great for walking out into the shallows and helping the kids in kayaks or whatever.